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August 26, 2014

Letter to the Editor

To the Editor,

This letter is in response to the "Monarch Butterflies in Trouble" post on Feb. 11th, 2014.

One of the icons of many childhood memories seems to be experiencing a population decline. Numbers of the dazzling orange & black Monarch Butterfly have dropped recently due to reduction in habitat in both their breeding and wintering sites.

It is well known that Monarchs east of the Rockies overwinter in a very few select sites in Mexico. Those along the Pacific Coast journey to Southern California. Not as much is known about those in the Utah Inter-mountain region.

We want to change that. Here's a chance for the residents of Cache Valley to help do a little scientific data collection.

The Cache Valley Wildlife Association (Utah member of the National Wildlife Federation), Stokes Nature Center and Bridgerland Audubon are sponsoring a Monarch larva/caterpillar collection project on Saturday, September 6th. All Cache Valley residents are asked to inspect milkweed plants for larvae within their own communities. If you are not certain as to what milkweed plants, or monarch larva, look like come to Nibley City Hall, 455 W. 3200 S., at 9:00am for a quick workshop. We'll be out collecting by 9:30.

Although Milkweed is not considered a noxious weed by the State or County, it is usually confined to roadside areas where the soil is somewhat moist. Most folks know that it is about three feet tall, has green leaves about six inches long which grow opposite of each other on the stem, will ooze a milky substance if injured, and often has seed pods which my students said resemble pickles. The milk is mildly toxic if taken internally, but the plant is critical to the survival of the Monarch as it is the only species where eggs are laid.

The harmless larva have yellow-white-black stripes, and have antenna near their head and tails. They are usually found on the underside of the leaves, and are quite fragile so don't drop them. Their max size is about two inches, but the smaller you find them, the better their survival.

Bring a container and lid large enough to hold several milkweed leaves, and transfer larva into that container very gently.

Call the number below to learn where to bring your larva, or email me to arrange a pickup in your community.

The larvae will be well cared for, and will morph into butterflies in about a week. We feed them for 3 days to make certain they are strong enough for long flights. Then they are marked with the small "Utah Code" color and pattern and released to begin their migration. If we can mark and release a good number of them, scientists in California may have a chance to spot them. Our Utah Code will help identify them even if they are up high in trees. Once a migration route and destination are determined people can be encouraged to plant milkweed along that pathway.

If you collect larva during other dates (like students bringing them to school in jars), please contact us so that we can mark them for you to release later.

Their migration is truly miraculous since their three proceeding generations have already died off, yet these new babies return to the places that their great-grandparents left in the Spring. Please take a couple of hours to check the milkweeds in your community.


Ron Hellstern
Nibley, Utah
435-512-6938

July 27, 2014

How You Can Tell If A Mantis Shrimp Has Color Vision???!!!

The FULL SPECTRUM OF LIGHT OR ELECTROMAGNETIC RADIATION is far wider than the narrow band of VISIBLE LIGHT which humans can see.  Light consists of small packets of energy called photons that simultaneously act like waves and particles.  Changes in the wavelength of light corresponds with changes in energy.  We perceive these different wavelengths/energy-states of light as colors.

Waves of light can be as long as several miles (radio waves, not to be confused with sound waves) or much shorter than the diameter of an atom (gamma and cosmic rays).  Humans can only see light of wavelengths ~370 nanometers to ~700 nanometers (nanometers are billionths of a meter and symbolized as nm) although it varies somewhat between people and can be quite reduced in people with color-blindness where one or more of the main pigments are missing.  Some birds and insects can see light waves as small as ~280 nm well into the ultraviolet range.  Some other organisms can see things slightly into the infrared.  Humans can only see the part of the light spectrum that we perceive as the rainbow of colors from red to blue, but we still feel infrared as heat and get a tan from ultraviolet rays.

Scientists can study the range of light that different organisms see by biochemically analyzing the light absorption of different photo-receptors, chromophores, pigments, proteins, oils and other molecules in their eyes that affect the range of light and resolution of their vision.  Two such applied methods are called spectrophotometry and electrophysiology.  Some information can also be gleaned from DNA sequences as well.  It is assumed that the light absorption properties of these bio-molecules reflects the range of vision that an organism actually experiences.  Humans, who see from about 370-700 nm, have four main light absorbing pigments that are contained in 3 types of cone cells (absorption peaks at 437 nm, blue cone, 533 nm, green cone, and 564 nm, red cone) and 1 type of rod cell (absorption peak at 498 nm).  These pigments are coded for in our genome.  The cone cells help us see in color and the rod cells help us see contrast in black, grey and white.  The figure below shows the light absorption range of these pigments and as you can see these pigments absorb light from about 370-700 nm. 

In other animals the number and absorption spectrums in their eyes may be quite different.  Take a finch for example.


We see that this finch has 4 main color sensing pigments with absorption patterns extending all of the way down into the ultraviolet.  Remember that humans only have 3 color absorbing pigments and one pigment that helps us with contrast and can't "detect" color.  If a human has 0,1 or 2 instead of the usual three cone cell pigments, they will be color blind maybe only seeing shades of grey, black and white...or maybe unable to see red and green or maybe some other combination of colors.  So what does a pigeon see with 4 pigments?  Do they see the world in more colors than humans?  Are humans unable to see things in nature that other organisms can?  And what do organisms experience for vision that have eyes with pigments that absorb into the ultraviolet and  infrared?  It is known in the case of some insect pollinators like bees and butterflies that they use ultraviolet to see flowers that are advertising that they want to be pollinated.  Some flowers "glow" in ultraviolet and display patterns that are thought to lead pollinators to where the nectar is.  When an insect gets the nectar and pollinates the flower, the ultraviolet markings often fade.  This seems to help insects distinguish between flowers that have already been visited for nectar and those that haven't.  Below are pictures of flowers in visible light (left frames) and in ultraviolet (right frames).  Just like a person who is color blind will miss cues that are in color, humans are unaware of many natural signs because our senses don't allow us to perceive all that there is to perceive.
 
 

I'm going to dig a little deeper into an interesting example of an organism with eyes that might very well see the world in details and colors we'll never even be able to imagine.  It is the Mantis Shrimp. 

Yes they really are that colorful!!!!!  Why did they evolve to be so colorful and why did such a complex vision system evolve in what humans would rather arrogantly consider such a simple creature?  How does such an elaborate vision sensory system affect their world view?  So many questions I have and not enough time to find out, but I will tell you a little bit about what I know about their amazing eyes!!

(For some strange mantis shrimp comic relief check out this video!)

 
As of 2014, Mantis Shrimp are known to have at least 16 photoreceptor pigments in their eyes (compared to 3 in humans) with 6 absorbing in the ultraviolet range.  This number is increased even further because some of the photoreceptor cells contain a variety of oil droplets (called cone cell droplets) that act like molecular filters that modify the range of light that a particular photoreceptor can absorb.  All these components together allows them to see a wide range of colors and probably many more fine gradations of color than humans.  It is also known that this array of receptors allows Mantis Shrimp to see linear and circular polarized light.



For what purpose they have so many photoreceptor pigments is unknown, but very intriguing (not to mention the sci fi's that could be written about the mystical powers of seeing with 16 color absorbing pigments...perhaps you could see spirits.).  Perhaps greater visual acuity is handy for surviving underwater or perhaps the Mantis Shrimp communicate through color signals.  No one knows with any certainty right now. Mantis Shrimp, however, are made even more amazing by the fact that they have two eyes that are subdivided into 3 each.  So instead of having binocular vision, they combine 6 images into one. 

What's weird about the molecular filters, which essentially increase the number of diverse photoreceptors in the Mantis Shrimp eyes, is that many of the chemical compounds are similar to ultraviolet "sunscreen" molecules that are present in other insect's eyes to protect them from ultraviolet damage.  It would be like co-opting the melanin in our skin, which makes our skin darker to protect us from the sun's ultraviolet rays, to make sun glasses that help us see more colors than we would normally.  Weird, right?  And it seems Mantis Shrimp don't actually manufacture these compounds in their bodies, but get them from their diet and somehow the chemicals get absorbed through the digestive tract into the blood stream where they find their way to the shrimp's eyes. 

Beyond just being a packet of energy that travels in waves, light can carry a lot of information like emotions, symbols and patterns, identification signs, communications, memories, etc. and a lot of the spectrum of light is beyond what our eyes can sense.  Are humans color blind to a vast world of tones and hues that other organisms can see and utilize?  If we could see more of the light spectrum, what would it tell us about the world we think we know?  How should the fact that many species, from chickens to squirrels to butterflies, can see far more colors than we can affect our interpretation of their behavior?  Why did vision evolve?  When and how did it evolve?  Is it a sense that is still evolving?  If color was always there, but it took so many millions and billions of years for eyes to evolve so that some organisms could see them what other phenomena are part of our world that we are ignorant of because we lack the sensory apparatus to perceive them?  And what does it imply, that though our biology is geared towards survival, we can and do use our biological tools to do so much more than survive, searching for meaning and understanding?  So many questions...and as of yet, so few answers.....
 

A good video about Mantis Shrimp vision can be found in the short video below.


-Seth Commichaux

Sources:

Osorio, D., Vorobyev, M., 2008.  A review of the evolution of animal colour vision and visual communication signals.  Vision Research.  Vol 48, pp 2042-2051.

Bok, M., Porter, M., Place, A., Cronin, T., 2014.  Biological Sunscreens Tune Polychromatic Ultraviolet Vision in Mantis Shrimp.  Current Biology.  Vol 24, pp 1-7.

https://www.youtube.com/watch?v=F5FEj9U-CJM

https://www.youtube.com/watch?v=glOsvm9t7ec

July 7, 2014

Spider, Anelosimus studiosus: To be or not to be social

You might think that sociality is a fixed biological trait for some species.  For instance, humans might be considered a social species as we instinctually form social units from clans and tribes to states and nations.  We also prefer social life, but all these factors are related to our biology.  We humans require a lot of care for many years to reach an age where we can take care of ourselves and societies seem to be the best way to incorporate and sustain as huge of a diversity of individuals as compose humanity.  But for some species like the spider Anelosimus studiosus sociality is dependent on the forces of environment and biology.  They are facultatively social, meaning that they will only form colonies under certain circumstances.  Most spider species that are social are web builders.  Amongst spiders social behavior is believed to have independently evolved 12-13 times.  These social spiders can be split up into two groups: colonial and cooperative.  In colonial species, many spiders share the same web, but they compete for territory and hunting rights on the communal web.  In cooperative species, many males, females and juveniles build/maintain a common web and rather than competing for hunting space on the web like colonial species, they cooperatively capture and share prey as well as collectively raise the next generation.  In cooperative species there are often more females than males.  Many spiders that aren't strictly social still have maternal care (that's right, motherhood has a long evolutionary history!).
Anelosimus studiosus

Anelosimus studiosus can be found from Argentina to New England.  The study I read dealt with differences in social behavior between populations of Anelosimus studiosus in Florida and Tennessee.  In Florida a typical colony was described as:
Composed of one adult female, her juvenile offspring and a few unrelated males that don't participate in web maintenance or communal prey capture.  The mother guards her egg case and feeds the newly emerged spiderlings through regurgitation.  As the juveniles grow, they increasingly participate in web maintenance and prey capture.  During this time, the mother accepts the entry of foreign juveniles and males into the nest while driving off intruding adult females.  The colonies are ephemeral because the spiderlings disperse upon reaching maturity and the mother eventually dies.  The young males often disperse first to go searching for mates while the young females are later driven off by their mother.  When the mother dies, it isn't unusual for another adult female to come along and use the web to raise her own offspring. (1)
In Tennessee, many colonies exist that are like the single-female-and-offspring ones described in Florida, but a new type of cooperative colony behavior appears that consists of:
Multiple females (3.7 females on average) cooperatively sharing a web, with cooperative foraging, communal brood care (baby spider daycare), and communal building/maintaining of the shared web. (1)
Why are there only single-female-and-offspring colonies down South in Florida?  And why is there a mixture of single-female-and-offspring colonies as well as multiple-female-and-offspring colonies further North in Tennessee?  Other trends to take note of with Anelosimus studiosus colonies are that the density of colonies goes down, and the spider webs get much bigger as you move from Florida-to-Tennessee.  Can we decipher any environmental, evolutionary and/or biological reasons that might explain these patterns?

A key to this puzzle is that juveniles require a lot of parental care for an extended period of time.  An advantage to communal parenting is that "if a mother dies in a multiple-female colony, the surviving females can foster the deceased female's brood." (1)  If the single mother of a single-female colony dies, so will her brood.  But if this is the case, why aren't all of the spiders communal?  Wouldn't natural selection favor communal parenting because it's a hedged-bet against the sometimes irrational environment?  Yes and no.  As it turns out, communal, adult females tend to have less offspring and have to spend more energy on colony activities on average than females who strike out on their own.  So the trade-off is between security
and reproductive success.  So what is it about Florida vs. Tennessee that makes being a lone mother vs. a communal mother good strategies, respectively?

A clue to the kind of sociality Anelosimus studiosus practices can be found in the environment.  Anelosimus studiosus spiders are most commonly found near water bodies like rivers and lakes.  From Tennessee to Florida there is great variation in air and, correspondingly, water temperature (Average air temperatures: @ latitude 26 degrees North in Southern Flordia is 23.5 degrees Celsius.  @ latitude 31 degrees North in Northern Florida is 19.5 degrees Celsius.  @ 36 degrees North in Tennessee is 14.5 degrees Celsius.)  It tends toward the waters being warmer in Florida and colder in Tennessee.  For Anelosimus studiosus as air and water temperature decreases so does the rate of development of the offspring (Mean time for juveniles to reach independence of mother: @ 22 degrees Celsius, 45.5 days.  @ 27 degrees Celsius, 28.7 days.  Thus about 5 degrees difference in average temperature affects almost a two-fold difference in rate of development!).  This means that where air and water temperatures are colder there is a greater likelihood that the mothers will die while raising their offspring because the cold causes the spiderlings to develop slower.  There is also the issue that there is higher juvenile mortality in colder climes.  Thus, where it is colder it is a good strategy to form colonies because if a mother dies the other mothers will pick up the slack.  Additionally, there is a higher risk that juveniles will die in colder places without proper care.  A community, evidently, is a better parent in these circumstances than an individual mother.

We can explain why the average size of colony webs becomes larger as you move north.  As you move North the proportion of multiple-female colonies goes up.  In Southern Florida there are only single-female webs, in Northern Florida there is only a small percentage of multiple-female colonies, and in Tennessee there is an even higher proportion of multiple-female colonies though it should be noted that for all locations single-female webs were the most common.  The seeming reason why colonies become more widely dispersed as you move North is that the environment becomes harsher by Anelosimus studiosus spider terms (meaning colder and perhaps less rain and vegetation). 


One of the interesting statement/conclusions in the paper I derived this blog from is that:
cooperation can allow populations to expand into and persist under harsher circumstances than individuals could otherwise endure.
It isn't that the spiders become tougher as you move North that allows them survive, but the fact that they work together toward a common destiny that allows them to endure harsher conditions.  Something to keep in mind for our lives I think.

A question that comes to my mind is if this example of facultative-sociality is just a case of instincts being switched-between based upon environmental conditions or if there is a level of recognition and agreement between the female spiders.  Do they recognize the potential for their own mortality in some harsh environments and the affect it would have on their brood?  Do the spiders recognize the utility of cooperating in these circumstances?  Afterall, not all of the spiders choose to form communities, even in colder climes.  Is it the less "fit" individuals that find it too hard to survive on their own in the cold locales who choose to band together as a solution, communally building/maintaining nests, cooperatively foraging, and communally caring for the baby spiders?  If this was true, it might be, as Darwin said in The Descent of Man, that humans became social because we were too weak to survive on our own.  If you're strong and self-sufficient you'd be better off not cooperating.  Yet it does seem to be weakness that brings us together, but united we become so much stronger than the sum of strong individuals competing for their own, selfish interests could ever be.

I hope to instill all my readers with a sense of complexity about all the creatures I speak of.  Assuming simplicity about things has been the source of much confusion and suffering.  It's taken a lot for people to see each other as more than black or white, or, good or evil.  Similarly, we too often assume that organisms other than humans are just instinctually-driven automatons.  But with just a little effort at delving into the world of those we don't understand, we soon find ourselves coming to the realization that nothing and no one can be simply defined and disregarded.

-Seth Commichaux

Sources Cited:
1) Jones, T., Riechert, S., Dalrymple, S., Parker, P., 2006.  Fostering Model Explains Variation in Levels of Sociality in a Spider System.  Animal Behavior vol. 73, pg 195-204.

June 11, 2014

Utah's Enlightened 50

Congratulations to Andree' Walker Bravo and the 49 other amazing Utahans who were recognized as the state's most enlightened 50 individuals!

The Community Foundation of Utah recognizes 50 individuals each year who make a difference in Utah through innovation, collaboration, and commitment to the common good!  

To view this year's E-50, please visit: http://utahcf.org/our-initiatives/The-e-50/.

June 10, 2014

Intergovernmental Panel on Climate Change: Blog #2 Summary of 2014 Report

MY PURPOSE

Global Warming/Climate Change is a contentious issue of modern times, but too important of an issue, with implications for everyone on Earth, to ignore and for us to remain uninformed about the scientific evidence and predictions about its consequences for us and the rest of the biosphere.  The scientific literature is building and consensus about its reality, as well as the evidence that its major driver is human activity, is growing.  Between 1970 and 1990 less than 1,000 scientific articles, books and conference proceedings were published about climate change in English.  However, by the end of 2012 there were over 102,000 and the number is dramatically increasing as more and more people are affected and become aware of global warming/climate change.  When you include scientific articles from Africa, Asia, Latin America, Europe and Australia, the number is even greater.

The Intergovernmental Panel on Climate Change (IPCC), a major organization founded by the United Nation's World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP), has recently released (March 31, 2014) one of the most comprehensive reports and analysis of climate change to date.  It also includes some of the most sophisticated, scientific models for predicting future outcomes of Global Warming/Climate change.  I've taken it upon myself to read as much of the IPCC report as I humanly can and to write a blog series summarizing and citing its findings to inform you about the current state of science on the issue of Global Warming/Climate Change.  It was reviewed by 1729 experts from 84 countries, had 436 contributing authors from 54 countries and over12,000 scientific references were cited.  The panel made a conscious effort to have a diverse and fair representation of authors and reviewers, both in terms of gender and national background, to minimize political, religious and cultural biases.

Summary and Citations From Technical Summary of Work Group I of IPCC

"The period 1983–2012 was very likely the warmest 30-year period of the last 800 years and likely the warmest 30-year period of the last 1400 years.  Although a certain amount of future climate change is already ‘in the system’ due to the current radiative imbalance caused by historical emissions and the long lifetime of some atmospheric forcing agents (greenhouse gases), societal choices can still have a very large effect on future...climate change.""

There's no doubt that the temperature of the Earth is increasing as it can be and has been directly measured for the past 150 years.  Indirectly, the temperature of the Earth and atmospheric gas concentrations can be measured from ice cores and other geological evidence.  This record shows a very strong correlation between atmospheric levels of carbon dioxide (CO2), as well as other greenhouse gases to a lesser extent, and the global mean temperature.  Because a sharp rise in greenhouse gases and global mean temperature has been observed starting around 1750 and the Industrial Revolution, when the mass combustion of fossil fuels producing copious amounts of carbon dioxide began, it can be inferred with great confidence that humans are causing global warming.

"Concentrations of the atmospheric greenhouse gases (GHGs) carbon dioxide (CO2), methane (CH4) and  nitrous oxide (N2O) in 2011 exceed the range of concentrations recorded in ice cores during the past 800,000 years."

"Between 1750 and 2011, CO2 emissions from fossil fuel combustion and cement production are estimated  from energy and fuel use statistics to have released ~750 trillion pounds of carbon. In 2002–2011, average fossil fuel and cement manufacturing emissions were ~16.6 trillion pounds of carbon per year, with an average  growth rate of 3.2% per year. This rate of increase of fossil fuel emissions is higher than during the 1990s (1.0% per year). In 2011, fossil fuel emissions released ~19 trillion pounds of carbon. Between 1750 and 2011, land use change (mainly deforestation), derived from land cover data and modelling, is estimated to have released ~360 trillion pounds of carbon. Land use change emissions between 2002 and 2011 are dominated by tropical deforestation, and are estimated at 1.8 trillion pounds of carbon per year, with possibly a small decrease from the 1990s due to lower reported forest loss during this decade. This estimate includes gross deforestation emissions of around 6 trillion pounds of carbon per year compensated by around  4 trillion pounds of carbon per year of forest regrowth in some regions, mainly abandoned agricultural land."

"Of the approximately 1.1 quadrillion pounds of carbon released to the atmosphere from fossil fuel and land use emissions from 1750 to 2011, 480 trillion pounds of carbon accumulated in the atmosphere.

"An independent line of evidence for the anthropogenic origin of the observed atmospheric CO2 increase
comes from the observed consistent decrease in atmospheric [and oceanic] oxygen (O2) content."

"The concentration of CH4 has increased by a factor of 2.5 since preindustrial times, from 722 parts per billion in 1750 to 1803 parts per billion in 2011.  There is very high confidence that the atmospheric CH4 increase during the Industrial Era is caused by anthropogenic activities. The massive  increase in the number of ruminants, the emissions from fossil fuel extraction and use, the expansion of rice paddy agriculture and the emissions from landfills and waste are the dominant anthropogenic CH4 sources. Anthropogenic emissions account for 50 to 65% of total emissions."

"Since pre-industrial times, the concentration of N2O in the atmosphere has increased by a factor of 1.2"

Earth absorbs more solar radiation because of the increased presence of these greenhouse gases and the Earth gets warmer as a result.  Interestingly though, "ocean warming dominates that total heating rate, with full ocean depth warming accounting for about 93%, and warming of the upper (0 to 700 m) ocean accounting for about 64%.  Melting ice (including Arctic sea ice, ice sheets and glaciers) and warming of the continents each account for 3% of the total. Warming of the atmosphere makes up the remaining 1%...........The majority of this additional heat is in the upper 700 m of the ocean, but there is also warming in the deep and abyssal ocean."

The ocean's ability to absorb heat is perhaps the one factor scientists underestimated when creating models for global warming in the past.  The ocean seems to be like a sponge for heat that has slowed the overall process of the warming of the Blue Planet thus far.  A kilogram of water and a kilogram of air could absorb the same amount of energy, but the air will increase in temperature far more than water will.  What's strange, but kind of cool, is that all the energy the ocean has absorbed hasn't raised its temperature much, but it has made it expand causing the sea level to rise slightly.  Remember that temperature is the measure of molecular motion.  When an object is hotter the molecules are moving faster and the object expands.

"The ocean has stored about 93% of the increase in energy in the climate system over recent decades, resulting in ocean thermal expansion and hence sea level rise............The associated thermal expansion of the ocean has contributed about 40% of the observed sea level rise since 1970."  (Overall, the ocean has been measured to have risen by about 8 inches over the period of 1901–2010.)

It's good for us, on land, that the ocean has absorbed most of the heat because if it hadn't we might've baked by now, but the bad thing is that the extra heat energy in the ocean affects the ocean currents.

"Recent observations have strengthened evidence for variability in major ocean circulation systems on time scales from years to decades.  It is very likely that the subtropical gyres in the North Pacific and South Pacific have expanded and strengthened since 1993."


Messing with ocean currents is a bad thing because ocean currents have a major impact on weather over the land.  It affects climate and temperature along the coast as well as cloud conditions and precipitation.

"Warming could lead to changes in ocean current patterns that could have drastic impacts on climate the world over.  Changing patterns of drought and monsoon as well as temperatures.  Could also effect the melting of permafrost which would allow for the decomposition of the organic carbon therein releasing much CO2 (carbon dioxide) and CH4 (methane).  [Resulting in the] retreat of the Boreal forest as well as causing shifts in the ranges of many animals and plants, which would exacerbate trends that we're already seeing, possibly leading to extinction of vulnerable species which are not that adaptable nor mobile."

In the most extreme cases it can cause super-powerful storms, like hurricanes, which can lead to great damage and loss of life.

"Over the satellite era, increases in the frequency and intensity of the strongest storms in the North Atlantic are robust."

In addition to causing stronger storms global warming will lead to higher evaporation rates and thus the average global humidity will rise as well as the amount of precipitation; even though there will be more precipitation overall, however, it is predicted to be more sporadic with increased intermittent times of drought.  In addition, "changes of average precipitation in a much warmer world will not be uniform, with some regions experiencing increases, and others with decreases or not much change at all."  This sporadic precipitation falling with greater intensity and the increased periods of intermittent drought will place a strain on crops and food production.

"High latitudes are very likely to experience greater amounts of precipitation....Many mid-latitude and subtropical arid and semi-arid regions will likely experience less precipitation and many moist mid-latitude regions will likely experience more precipitation by the end of this century."

The warming of the oceans and atmosphere acting in synergy have caused glaciers and the polar ice caps to recede, the extent of permafrost to retreat, as well as a reduction in the amount of snow cover in the Northern Hemisphere during winters.

"there is very high confidence that the Arctic sea ice extent (annual, multi-year and perennial) decreased over the period 1979–2012. The rate of the annual decrease was very likely between 3.5 and  4.1% per decade."

"There is high confidence that the average winter sea ice thickness within the Arctic Basin decreased between 1980 and 2008. The average decrease was likely between 1.3 m and 2.3 m."

It could be possible that the Arctic ice cap will change from perennially covered to seasonally covered in our lifetimes.  This would wreak havoc on the animals that call the Arctic ice their home.

 
"There is high confidence that the Antarctic ice sheet has been losing ice during the last two decades"

"The available evidence indicates that global warming beyond a threshold would lead to the near-complete loss of the Greenland ice sheet over a millennium or longer, causing a global mean sea level rise of approximately 7 m (~23 feet)."

Even though we are adding a lot of carbon dioxide and other greenhouse gases into the atmosphere, resulting in the warming of the Earth and its oceans, a great proportion of the carbon we've released has ended up in the biosphere (mostly through plants and other photosynthetic organisms), oceans and sediments.  These carbon sinks have slowed the rise of carbon dioxide in the atmosphere and thus have slowed the rate of climate change (this is why ecosystem services are so important!)

"The human caused excess of CO2 in the atmosphere is partly removed from the atmosphere by carbon sinks in land ecosystems and in the ocean, currently leaving less than half of the CO2 emissions in the atmosphere. Natural carbon sinks are due to physical, biological and chemical processes acting on different time scales. An excess of atmospheric CO2 supports photosynthetic CO2 fixation by plants that is stored as plant biomass or in the soil. The residence times of stored carbon on land depends on the compartments (plant/soil) and composition of the organic carbon, with time horizons varying from days to centuries. The increased storage in terrestrial ecosystems not affected by land use change is likely to be caused by enhanced photosynthesis at higher CO2 levels and nitrogen deposition, and changes in climate favoring carbon sinks such as longer growing seasons in mid-to-high latitudes."

"An excess of atmospheric CO2 absorbed by land ecosystems gets stored as organic matter in diverse carbon pools, from short-lived (leaves, fine roots) to long-lived (stems, soil carbon)."

 

"The uptake of anthropogenic CO2 by the ocean is primarily a response to increasing CO2 in the atmosphere. Excess atmospheric CO2 absorbed by the surface ocean or transported to the ocean through aquatic systems (e.g., rivers, groundwaters) gets buried in coastal sediments or transported to deep waters where it is stored for decades to centuries. The deep ocean carbon can dissolve ocean carbonate sediments to store excess CO2 on time scales of centuries to millennia. Within a 1,000 years, the remaining atmospheric fraction of the CO2 emissions will be between 15 and 40%, depending on the amount of carbon released. On geological time scales of 10,000 years or longer, additional CO2 is removed very slowly from the atmosphere by rock weathering, pulling the remaining atmospheric CO2 fraction down to 10 to 25% after 10,000 years."  An unfortunate side-effect of the ocean absorbing CO2 is that it acidifies the water (the ocean has seen a 26% increase in acidity over the past 250 years).  This is bad because the extra acidity dissolves the coral reefs, which can take thousands of years for the organisms to build, and any marine organisms that make calcium carbonate shells.

In fact, increased CO2 in the atmosphere is predicted to increase the amount of plant biomass on Earth, especially in desert areas through a phenomena called the Carbon Dioxide Fertilization Effect.  CO2 is a limiting nutrient in many environments and it reduces the amount of growth in plants, but with an excess of CO2 in the atmosphere from the burning of fossil fuels plants put on more biomass until other nutrients in the soil like nitrogen and phosphorous become limiting to growth.  One might think that plants are going to offset global warming by up-taking the excess CO2, but in fact we are producing too much greenhouse gases for plant growth to keep up and offset our activities.  Additionally, the accelerated rate of plant growth due to higher atmospheric CO2 levels is bad for soils because it will cause nitrogen and phosphorous depletion which are essential nutrients for building proteins and nucleic acids.

"It is very likely, based on new experimental results and modelling, that nutrient shortage will limit the effect of rising atmospheric CO2 on future land carbon sinks. There is high confidence that low nitrogen availability will limit carbon storage on land even when considering anthropogenic nitrogen deposition. The role of phosphorus limitation is more uncertain."

Some skeptics wonder if other natural forces might be causing global warming other than human activity.  They might question whether the sun has increased its energy output or if volcanoes have released more carbon dioxide lately than normal.

It is true that the Earth's climate oscillates over time and that in the past there were periods of higher temperatures with higher atmospheric carbon dioxide levels than modern times.


"During warm intervals of the mid Pliocene (3.3 to 3.0 million years ago), there's medium confidence that global mean temperatures were 1.9°C to 3.6°C warmer than the pre-industrial climate and with carbon dioxide (CO2) levels that were between 350 and 450 ppm (modern times is at about 400 ppm), there is high confidence that the global mean sea level was above present, but by no more than 20m (65 feet)."

"There is very high confidence that the maximum global mean sea level during the last interglacial period (129 to 116,000 years ago) was,  for several thousand years, at least 5m (16.25 feet) higher than present and high confidence that it did not exceed 10m (323.5 feet) above present, implying substantial contributions from the Greenland and Antarctic ice sheets. This change in sea level occurred in the context of different orbital forcing and with high-latitude surface temperature, averaged over several thousand years, at least 2°C warmer than present."

"During the Early  Eocene (52 to 48 million years ago), atmospheric CO2 concentration exceeded about 1000 ppm and the global mean temperature was 9°C to 14°C higher than for pre-industrial conditions."

It is also true that volcanic eruptions and changes in the sun's solar output have effects on the Earth's climate, but the record is pretty clear that these variables are not driving modern climate change.  In truth, volcanoes can often have a cooling effect on the Earth's climate by blocking the sunlight with particulate matter.

"Explosive volcanic eruptions (such as El Chichón in Mexico in 1982 and Mt Pinatubo in the Philippines in 1991) can inject sulphur dioxide into the stratosphere, giving rise to stratospheric aerosol, which persists for several years. Stratospheric aerosol reflects some of the incoming solar radiation and thus gives a negative forcing (negative forcing is the same as global cooling in this context).  Large tropical volcanic eruptions have played an important role in driving annual to decadal scale climate change during the Industrial Era owing to their sometimes very large negative RF."  This is saying that volcanoes do and have played an important role in climate change over the past 250 years, but the majors effect on climate has been cooling.

"The emissions of CO2 from volcanic eruptions are at least 100 times smaller than anthropogenic emissions, and inconsequential for climate on century time scales."

"Solar forcing is the only known natural forcing acting to warm the climate over the 1951–2010 period but it has increased much less than greenhouse-gas-induced-climate-forcing, and the observed pattern of long-term tropospheric warming and stratospheric cooling is not consistent with the expected response to solar irradiance variations. Considering this evidence together with the assessed contribution of natural forcings to observed trends over this period, it is assessed that the contribution from solar forcing to the observed global warming since 1951 is extremely unlikely to be larger than that from greenhouse-gas-induced-climate-forcing. Because solar forcing has very likely decreased over a period with direct satellite measurements of solar output from 1986 to 2008, there is high confidence that changes in total solar irradiance have not contributed to global warming during that period. However, there is medium confidence that the 11-year cycle of solar variability influences decadal climate fluctuations in some regions through amplifying mechanisms."

"Solar and volcanic forcings are the two dominant natural (as opposed to human-caused) contributors to global climate change during the Industrial Era, but there is strong evidence that excludes solar forcing, volcanoes and internal variability as the strongest drivers of warming since 1950."

CONCLUSION

All this evidence pretty overwhelmingly proves that humans are the major driver of modern climate change/global warming and it is being done mainly through the burning of fossil fuels which produces the major culprit greenhouse gases CO2 (carbon dioxide), CH4 (methane), and NO2.

In the next blog of this series I will summarize the last part of the IPCC report which talks more specifically about the impacts to human societies and the environment as well as recommendations for courses of action by the international community to head off this potentially devastating, impending disaster known as climate change/global warming.

-Seth Commichaux

Source Cited:
Technical Summary of Work Group I of IPCC
http://www.climatechange2013.org/images/report/WG1AR5_TS_FINAL.pdf

May 19, 2014

More Reasons To Go Organic: The Dirty Dozen Crops That Use The Most Pesticides



There are many reasons why organically grown crops are becoming more and more desirable.  For one, it tends to support local farmers, better wages and fairer trade.  But another reason, that this article deals with directly, is about the benefits to our health.  Our health referring not just to those who consume the produce of others labor, but also the health of those who grow our food and who take it to market.

I both listened to a podcast and read a new report by the Environmental Working Group which I will summarize for you here if you don't find time to listen to it.  I will list the links in my blog if you want the whole, unabridged story from the source.  Hopefully, my commentary will encourage you to look at the source for yourself as we live in an age where there is too much secondhand knowledge.

The story I listened to was a podcast by Living On Earth about a new study by the Environmental Working Group that lists, from most-to-least, the 48 food crops that have the most residual pesticides that can't be washed off.  Here is the link to the story: ( http://www.loe.org/shows/segments.html?programID=14-P13-00019&segmentID=3 ).  I emphasize here CAN'T BE WASHED OFF!  Therefore, if you ingest these crops you will also be ingesting the pesticides even if you try your darnedest to clean them. 

The top 12 crops (the dirty dozen), ordered from most-to-least, with the most residual pesticides are:

1) apples
2) strawberries
3) grapes
4) celery
5) peaches
6) spinach
7) sweet bell peppers
8) nectarines-imported
9) cucumbers
10) cherry tomatoes
11) snap peas-imported
12) potatoes

The top 12 cleanest crops, from cleanest-to-less-clean, are:

1) avocados
2) sweet corn
3) pineapples
4) cabbage
5) sweet peas-frozen
6) onions
7) asparagus
8) mangoes
9) papayas
10) kiwis
11) eggplants
12) grapefruit

Link to ratings of the full 48 food crop list by pesticide use.  Keep in mind that these are pesticides that cannot be washed off!
http://www.ewg.org/foodnews/list.php#

Link to the full report by the Environmental Working Group is worth a browsing as it addresses some of the failures of the EPA to regulate agribusiness and to inform the public about what we are eating and what potential risks might be associated with it.
http://www.ewg.org/foodnews/summary.php

Some quotable quotes from the Executive Summary:

Parents' concerns have been validated by the American Academy of Pediatrics, which in 2012 issued an important report that said that children have "unique susceptibilities to [pesticide residues'] potential toxicity." The pediatricians' organization cited research that linked pesticide exposures in early life and "pediatric cancers, decreased cognitive function, and behavioral problems."

European regulators are several steps ahead of their American counterparts. Over the past several years, they have raised new questions about the safety and ecological dangers of a group of pesticides known as neonicotinoids. These chemicals are suspected of disrupting human brain development and of killing honeybees and other beneficial insects.

USDA testing has found neonicotinoid residues on about 20 percent of all produce samples and as much as 60 percent of broccoli, cauliflower, grapes, spinach and summer squash.

The European Commission has banned diphenylamine, DPA for short, on fruit raised in the 28 European Union member states and has imposed tight restrictions on imported fruit. DPA, a growth regulator and antioxidant, is applied after harvest to most apples conventionally grown in the U.S. and to some U.S.-grown pears, to prevent the fruit skin from discoloring during months of cold storage.

U.S. officials have not followed the Europeans in restricting either neonicotinoids or DPA.

Every sample of imported nectarines and 99 percent of apple samples tested positive for at least one pesticide residue.

The average potato had more pesticides by weight than any other food.

A single grape sample contained 15 pesticides.

Single samples of celery, cherry tomatoes, imported snap peas and strawberries showed 13 different pesticides apiece.

Avocados were the cleanest: only 1 percent of avocado samples showed any detectable pesticides.

Some 89 percent of pineapples, 82 percent of kiwi, 80 percent of papayas, 88 percent of mango and 61 percent of cantaloupe had no residues.

No single fruit sample from the Clean Fifteen™ tested positive for more than 4 types of pesticides.

Detecting multiple pesticide residues is extremely rare on Clean Fifteen™ vegetables. Only 5.5 percent of Clean Fifteen samples had two or more pesticides.

Leafy greens - kale and collard greens - and hot peppers do not meet traditional Dirty Dozen™ ranking criteria but were frequently contaminated with insecticides that are toxic to the human nervous system. EWG recommends that people who eat a lot of these foods buy organic instead.

The USDA's most recent pesticide monitoring data included hundreds of samples of applesauce, carrots, peaches and peas packaged as baby food (USDA 2014). Because cooking reduces levels of pesticides and baby food is cooked before packaging, it tends to contain lower pesticide residues than comparable raw produce.

The U.S. has no special rules for pesticide residues in baby food. 

The USDA detected 10 different pesticides on at least 5 percent of 777 samples of peach baby food sold in the U.S (USDA 2014). Nearly a third of the peach baby food samples would violate the European guideline for pesticides in baby food because they contain one or several pesticides at concentrations of 0.01 part per million or higher.

The USDA tested 396 baby food applesauce samples for five pesticides (USDA 2014). Some 18 percent of the samples contained acetamiprid, a neonicotinoid pesticide that EC regulators singled out for additional toxicity testing because it might disrupt the developing nervous system (EFSA 2013). Another 17 percent of the samples contained carbendiazim, a fungicide.

The USDA found six pesticides in apple juice, a staple of many children's diets (USDA 2014). About 14 percent of the apple juice samples contained DPA.

Editorial Comment:

The most outrageous aspect of pesticide use, in my opinion, isn't about consumption, but production.  The farm workers of the United States of America and worldwide, who grow, cultivate and harvest the produce that finds its way to our tables, often tend to be poor, underpaid, over-worked, benefit-less, exploited, exposed to unreasonably hazardous conditions without protection and (at least in the case of the U.S.) are right-less, subject to deportation and to being torn apart from their friends and family.  From many of the reports cited by the Environmental Working Group and from reports and scientific articles that I have personally read, it tends to be the farm laborers in the USA who are most adversely affected by pesticide use, not consumers.  These people who have much higher exposure to these poisons have much higher rates of cancer, birth defects and other health issues (such as respiratory and reproductive problems) than the average person in the USA.  This might be a mere coincidence or it might be more than an anomalous correlation that points to the toxicity of the pesticides which are used and that these people are disproportionately exposed to.

What might even be more unjust than the exploitation of these people for our cheap food is the fact that it is known that many of these substances are particularly detrimental to pregnant women and to developing fetuses and children.  It seems unjust enough to exploit desperate people, but then to destroy the hope they've worked for, the well-being of and betterment of life for their children, by causing mental and physical development defects through the irresponsible use of toxins seems to demand a change in social policy.

On a different note I might add here that there are more responsible ways of growing food than the indiscriminate use of pesticides.  It may not be possible to grow all food crops for 7+ billion people on a totally organic basis, but there are many alternatives that would allow for organically grown crops to supplement much of the yield that would still require pesticides.  But for this transition to occur, organically grown foods would have to be cheaper and more accessible for all members of society.  This might require a subsidy program by the government, but seeing how the government sees fit to subsidize other socially-necessary commodities like oil and natural gas extraction, I don't see how they could rationalize not subsidizing something as socially-necessary as food.

-Seth Commichaux

April 21, 2014

What Does The Environment Do For Us?

A lot of people that I've talked to or overheard in conversation when talking about why the environment should be saved in a "wilderness" state often give the beauty of nature or the transcendental experience of being in a wilder setting as reasons.  Many find peace of mind, artistic inspiration and a sense of connectedness with the universe wandering in the great out-of-doors.  Some also note that you need to save wilderness areas to provide habitat for the animals and plants that call those places home.  If you lose those places you'll lose the animals and plants as well.

 

All of these reasons are good reasons to preserve our natural inheritance, but for people who are more business oriented or who don't enjoy nature that much might not be convinced that these reasons are sufficient to override the necessity for development and resource harvesting.

I was reading an interesting paper from BioScience journal called, "Linking Ecology and Economics for Ecosystem Management" that tried to take a more quantitative approach to valuing ecosystem services for the purpose of taking into account what monetary value is being lost by developing natural ecosystems.  

A satellite image of deforestation
At the most fundamental level humans and most other organisms (perhaps some bacteria are exceptions) could not survive long without the complex networks of services that we provide for one another.  All lifeforms are totally interdependent and are players in complex cycles where everything gets used and recycled.
 

Ecosystem services are all the benefits that humans obtain from ecosystems and the biosphere.  These services come in many forms and we'll go through many examples so that the next time someone, who maybe doesn't appreciate the beauty of nature, asks you why the environment should be preserved you'll be able to give some other, more utilitarian/anthropocentric, reasons.

Beyond beauty and the artistic/spiritual value of nature, and beyond the fact that many plants and animals call these wild places home, many people value nature for the purpose of all kinds of recreation from camping, hiking, canoeing, biking and other outdoor sports to photography, birdwatching, site-seeing, etc.  

 

At a more utilitarian level, we receive all of the necessities of life from the environment.  Everything we see in our homes and our communities came from the environment.  Perhaps it was metal ore from deep in the ground that was used to make railroad tracks, skyscrapers, bridges, machines, tools, parts in our cellphones and computers.  Perhaps it was coal, oil, or natural gas that now is being combusted to move our cars, trains, planes or to produce electricity.  Maybe it was wood cut down in the Pacific Northwest or the Amazonian Rainforest that is now our tables, desks, cupboards, bookshelves, doors or house-frames.  Maybe it was some plant harvested for food, drink, chemicals, lotion, medicine or fuel.  Maybe it was a medicinal herb that helps soothe a cold or a compound produced by a bacteria with anti-cancer properties.  Maybe it was some animal that was slaughtered for food, clothing, or apparel.  Everything comes from the environment whether near or far.  It can be fun to look at something like a computer and to try to deconstruct it down to its components and trying to guess where it all came from, how it was made, and who made it.

The provisioning of raw resources are more commonplace services that the environment provides, that many of us are aware of, though we may often forget them and take their complexity for granted (for instance, we might eat a cow, but what was necessary for that cow to survive?  It needed to eat grass, the grass needs sunlight, air, water, and good soil which requires bacteria and fungi which make nutrients accessible as well as worms that help nutrients cycle underground, and these worms, fungi and bacteria need things, etc.  It can get complex fast.), but there are other ecosystem services that many of us are not aware of though they are just as important, if not even more important.  

Nutrient cycling is one such extremely important, but ofter overlooked, ecosystem service that bacteria, fungi, protozoans, nematodes, and various other microorganisms as well as worms, and burrowing animals, etc., provide.  Nutrient cycling helps keep the soil fertile and often helps the soil retain moisture.  This is important for our crops as well as all plants which are the base of many food webs.  If nutrients didn't cycle, as a plant would grow its roots would deplete the soil in its vicinity.  The roots could grow longer to reach nutrients further and further away, but there is a limit to how long roots can grow.  The roots could also divide into a finer network to extract nutrients in the in-between places, but there is a limit to how finely divided a root system can become.  Thus, rather than the plant depleting its local area and eternally growing to reach nutrients further-and-further away, the nutrients come to the plant.  Bacteria and fungi make nutrients from atmospheric gases and transport those nutrients to plants in exchange for photosynthetically made sugars from the plant; worms and burrowing animals move nutrients from deeper levels to higher levels; decomposers breakdown dead organic matter into nutrients that the plant can use.  All of these processes make nutrients available to plants without the plant having to move or invest energy in growth.

 
Pollination and seed dispersal are another important, but often overlooked ecosystem service.  According to the Natural Resources Defense Council approximately 30% of the world's crops are pollinated by bees alone.  Many plants require pollinators from bats and birds, to bees and butterflies to sexually reproduce.  Without this pollinator service many plants would soon die off and this would effect many other things like soil quality, climate, the gas composition of the atmosphere, and the number and kind of organisms that live off of plant matter in some way just to name a few.

Seed dispersion is necessary for many plants to increase their range size, to maintain genetic diversity, to increase the odds of rooting in fertile ground, to reduce local competition for resources, etc. and can be performed by insects, amphibians, reptiles, birds, and mammals including humans.


Climate Control, atmospheric regulation and the regulation of the hydrological cycle are yet another often overlooked ecosystem services provided by many organisms.  These services are perhaps provided more subtly and seem more abstract, but in the absence of a favorable climate, atmosphere and water cycle much of life on Earth would perish.  We all contribute to atmospheric regulation.  All organisms respire and produce CO2 or a CO2 equivalent (even plants produce some CO2).  Other organisms, like plants, algae and some bacteria make atmospheric oxygen out of CO2, while other bacteria make methane and nitrogen gas.  Just how the chemical composition of the atmosphere is maintained is still somewhat of a mystery, but we all contribute in some way and benefit too.

Organisms effect their climate.  Let's take a forest as an example.  A forest tends to be cooler and more humid than a city.  There is even some evidence that forests, because they are cooler and more humid, might generate some of their own rain in a way similar to "lake effect" precipitation.  Additionally, because forests retain moisture, they tend to help water percolate deep and recharge underground aquifers.  This process also helps purify water.  For all of these reasons when forests like the rain forests are clear-cut the land tends to become much drier and hotter, prone to desertification and fires.  Thus, many of the climates we enjoy on Earth might, in part, be created by the organisms around us and we would be wise to maintain them so that all of Earth doesn't become a harsh, hot, barren desert. 

Organisms who provide biological waste regulation services just like your local garbage collector tend to be under-acknowledged for their efforts.  Decomposers and nutrient recyclers are constantly at work.  Could you imagine living on an Earth where nothing dead ever broke down?  The Earth would be a heap of all the bodies of the plants, animals and microorganisms that ever lived with no room to live and with all the nutrients tied up.  Luckily, there are decomposers and recycling-minded organisms (like fungi and bacteria) who break down dead things into their elemental parts so that the nutrients can be re-used to make the bodies of organisms living, growing and still yet to be born.

Other organisms get rid of, detoxify or store our waste and pollution.  Wetlands are very good at removing pollutants, fertilizers, pesticides and other chemicals from rivers and lakes.  Other organisms help purify the air by removing pollutants and storing them in their bodies.  Many bacteria in the soil break down many human-made chemicals and remove molecules from water, in a purifying process, as it percolates to underground aquifers that we then can use as drinking water or irrigation water.

Other ecosystem services also go unnoticed like the disturbance mitigation wetlands and mangrove forests provide against flooding and tidal waves, or wind breaking by trees, or the prevention of landslides and erosion by the roots of plants. 

Biological regulation like pest control by predators is an important ecosystem service that we receive.  If there were no checks and balances on organisms like mosquitoes, termites, mice, bacteria, pathogens, etc., Earth would be a very different place (probably a very miserable one).  Biodiversity is one of the best protections against disease-causing organisms because it controls their populations and limits the extent of their range as well as provides competition for their niche.


The biological world also provides genetic resources which are important for resilience.  Diversity is necessary for life to survive a dynamic and sometimes harsh environment.  In agriculture, crosses are often made in the lab between ancestral corn plants and modern versions of corn when varieties need to be selected that can survive droughts better or that can survive the attacks of certain pests better, for example.  Lately, scientists have exploited the genetic diversity of bacterial toxins for crop production by putting those bacterial genes in corn and other crops as an insecticide.

Science and society also benefit from the intellectual ecosystem services of education and imagination.  Would we ever have thought of the possibility of flying had we not seen birds and insects flying?  Would we ever have developed anti-biotics had Alexander Flemming not noticed that a fungus was creating compounds that were keeping bacterial colonies at bay?  Will we develop renewable energy sources in the future mimicking the processes of photosynthesis?

For all of the ecosystem services that organisms on Earth provide for us how many more are provided that we're unaware of?  Is it possible that there are many other services provided that we're not aware of?  Is this reason enough to try and protect the biodiversity that exists on Earth?

The Earth and its organisms do so many things for us, to keep us alive, that we don't have to work or pay for.  These ecosystem services range from artistic inspiration and peace of mind, to water filtration, climate control, atmospheric chemistry regulation and the provisioning of food.  It can truly be said that we humans are totally dependent upon the organisms of this Earth for survival.  It's probably wise for us to keep that in mind as we go forward in this modern age.

-Seth Commichaux

April 8, 2014

Intergovernmental Panel on Climate Change: Blog Series Summary of 2014 Report

MY PURPOSE

Global Warming/Climate Change is a contentious issue of modern times, but too important of an issue, with implications for everyone on Earth, to ignore and for us to remain uninformed about the scientific evidence and predictions about its consequences for us and the rest of the biosphere.  The scientific literature is building and consensus about its reality, as well as the evidence that its major driver is human activity, is growing.  Between 1970 and 1990 less than 1,000 scientific articles, books and conference proceedings were published about climate change in English.  However, by the end of 2012 there were over 102,000 and the number is dramatically increasing as more and more people are affected and become aware of global warming/climate change.  When you include scientific articles from Africa, Asia, Latin America, Europe and Australia, the number is even greater. (2)

The Intergovernmental Panel on Climate Change (IPCC), a major organization founded by the United Nation's World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP), has recently released (March 31, 2014) one of the most comprehensive reports and analysis of climate change to date.  It also includes some of the most sophisticated, scientific models for predicting future outcomes of Global Warming/Climate change.  I've taken it upon myself to read as much of the IPCC report as I humanly can and to write a blog series summarizing and citing its findings to inform you about the current state of science on the issue of Global Warming/Climate Change.  It was reviewed by 1729 experts from 84 countries, had 436 contributing authors from 54 countries and over12,000 scientific references were cited.  The panel made a conscious effort to have a diverse and fair representation of authors and reviewers, both in terms of gender and national background, to minimize political, religious and cultural biases. (1)

SUMMARY AND CITINGS FROM IPCC REPORT (WORKING GROUP 2)

 CHAPTER 1. POINT OF DEPARTURE

"Warming of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia.  Human influence on the climate system is clear; it has been detected in warming of the atmosphere and the ocean, in changes in the global water cycle, in reductions in snow and ice, in global mean sea level rise, and in changes in some climate extremes." (2)  I mention here also the acidification of the ocean and the detectable rise of greenhouse gases in the atmosphere such as carbon dioxide and methane that can be directly attributed to the combustion of fossil fuels.

It is likely that the global mean temperature will continue to rise throughout the 21st century and that the "length, frequency, and/or intensity of warm spells or heat waves will increase over most land areas."  "It is likely that the frequency of heavy precipitation will increase in the 21st century over many areas of the globe."  (2)

Figure 1.  Showing the strong correlation between mean global temperature and atmospheric carbon dioxide increase
 

Figure 2. The periodic oscillations of carbon dioxide over the past 400,000 years and the uncharacteristic spike who's beginning strongly correlates with the beginning of the industrial revolution.
Three goals of the Working Group (WG) who wrote the IPCC report:
1) Detect and identify impacts of climate change
2) Identify what of climate change can be attributed to human activity
3) Predict and project effects of climate change into the 21st century

"As basic resources such as energy, land, food or water become threatened, inequalities and unfairness may deepen leading to maladaptation and new forms of vulnerability.  Responses to climate change may have consequences and outcomes that favor certain populations or regions.  For example, there are increasing cases of land-grabbing and large acquisitions of land or water rights for industrial agriculture, mitigation projects or biofuels that have negative consequences on local and marginalized communities." (2)

• Risks to Unique and Threatened Systems: biodiversity and many ecosystems such as polar and high mountain communities are at increased risk of adverse impacts from temperatures increase
• Risks Associated with Extreme Weather Events:  projected increases in droughts, heat waves, extreme high-water coastal events, a rise in sea-levels and floods, as well as their adverse impacts.
• Risks Associated with the Distribution of Impacts: “There are sharp differences across regions and those in the weakest economic position are often the most vulnerable to climate change."  However, the poor and elderly are vulnerable groups in developed and developing countries alike.
• Risks Associated with Aggregate Impacts: Whatever benefits come from less-severe winters and cold-spells will be dwarfed by the negative costs of excessive heat and more severe weather patterns.

Even if we adjust our behavior now we will not be able to avoid further impacts of climate change for decades to come, but if we don't adjust our behavior the magnitude of effects caused by climate change will likely make "adaptation impossible for some natural systems;" while humanity will likely suffer "very high social and economic costs." (2)

"the deployment of renewable energy technologies has increased rapidly in recent years, often associated with cost reductions that are expected to continue with advancing technology. Despite the small contribution of renewable energy to current energy supplies.....the global potential of renewable energy...(is)...substantially higher than the global energy demand. It is therefore not the technological potential of renewable energy that constrains its development, but rather economic factors, system integration, constraints, public acceptance, and sustainability concerns." (2)

"Economic losses from weather- and climate-related disasters have increased, but with large spatial and (temporal) variability."  Disaster losses, fatality rates and economic losses due to climate related events are higher in developing countries.  "From 1970-2008....more than 95% of deaths from natural disasters were in developing countries."  "environmental degradation, unplanned urbanization, failure of governance or reduction of livelihood options result in increased exposure and vulnerability to disasters."  "improvements in governance and technology...(and)...more transformational changes are essential for reducing risk from climate extremes." (2)

SCIENTIFIC INFORMATION CITED FROM CHAPTER 1. POINT OF DEPARTURE

Greenhouse gases and climate forcing:

"Human activities are the dominant cause of the observed increase in well mixed greenhouse gases (GHGs) since 1750 and of the consequent increase in climate forcing." (2)
  1. GHGs have continued to increase and at an accelerated rate since 1970. 
  2. Present-day (2011) abundances of CO2, CH4, and N2O exceed the range over the past
    800,000 years found in ice cores.
  3. Annual emission of CO2 from fossil fuels and cement production was 9.5 GtC in 2011, 54% above the 1990 level.
  4. More than 20% of added CO2 will remain in the atmosphere for longer than 1000 years.
  5. Cumulative CO2 emissions from 1750 to 2011 are 365 GtC (fossil fuel and cement) plus 180 GtC (deforestation and other land-use change). This 545 GtC represents about half of the 1000 GtC total that can be emitted and still keep global warming under 2 °C relative to the reference period 1861-1880.
  6. ***In 2010, GHG emissions surpassed 50 Gt CO2-eq (13.6 GtC), higher than in any previous year  since 1750. Most of the emission growth between 2000 and 2010 came from fossil-fuel use in the energy and industry sectors, and took place in emerging economies. This emission growth  was not met by significant GHG emission cuts in the industrialized country group, which continued to dominate historical long-term contributions to global CO2 emissions. In 2010,  median per capita GHG emissions in high income countries were roughly ten times higher than in low-income countries.***
Surface Temperatures:
  1. Global mean surface temperature increased by 0.85 [0.65 to 1.06] °C over the period 1880–
    2012 (linear trend) and by 0.72°C over the period 1951–2012. Each of the last three decades (from 1983 to 2012) has been successively warmer than any preceding decade since 1850. 
  2. More than half of the 1951-2010 temperature increase is due to the observed
    anthropogenic increase in GHG (Greenhouse Gases).
  3. The projected near term (2016-2035) mean surface temperature increase is 0.9–1.3 °C, and the long term (2081-2100) ranges from 0.9–2.3 °C to 3.2–5.4 °C.
  4. Global temperatures during the last interglacial period (~120,000 years ago) were never more than 2°C higher than pre-industrial levels. By 2050 the global warming range is 1.5°C to 2.3°C above the 1850-1900 period based on the range across all...models.
Precipitation:
  1. Precipitation (global annual averages) will increase as temperatures increase, and the contrast between dry and wet regions and that between wet and dry seasons will increase over most of the globe.
  2. High latitudes will experience more precipitation;many moist mid latitude regions will also experience more; while many mid latitude and subtropical arid and semiarid regions will experience less.
  Extreme temperatures and precipitation:
  1. Extreme high temperatures (20-year return values) are projected to increase at a rate similar to or greater than the rate of increase of summer mean temperatures in most regions.
  2. In the long term heat waves will occur at higher frequency and longer duration in response to increased seasonal mean temperatures.
  3. With global warming, the frequency and intensity of heavy/extreme precipitation events will increase over most mid latitude land and over wet tropical regions.
Floods and droughts:
  1. In many regions, historical droughts (last 1000 years) and historical floods (last 500 years)
    have been more severe than those observed since 1900.
  2. The frequency and intensity of drought has increased in the Mediterranean and West Africa, and it has decreased in central North America and north-west Australia since 1950.
  3. There is low confidence in attributing drought changes to human influence.
Tropical cyclones, storms, and wave heights:
  1. The frequency and intensity of the strongest tropical cyclones in the North Atlantic has increased since the 1970s.
  2. The maximum wind speed and precipitation rates of tropical cyclones will increase.
  3. Circulation features have moved poleward since the 1970s, including a poleward shift of storm tracks and jet streams.
  4. With global warming, a shift to more intense individual storms and fewer weak storms is projected.
  5. Mean significant wave height has increased over much of the Atlantic north of 45°N since 1950, with winter season trends of up to 20 cm/decade.
  6. Wave heights and the duration of the wave season will increase in the Arctic Ocean as a result of reduced sea-ice extent. Wave heights will increase in the Southern Ocean as a result of enhanced wind speeds.
Ocean warming, stratification and circulation:
  1. Overall, the ocean has warmed throughout most of its depth over some periods since 1950, and this warming accounts for about 93% of the increase in Earth's energy inventory between 1971 and 2010.
  2. The upper ocean above 700 m has warmed from 1971 to 2010, and the thermal stratification has increased by about 4% above 200 m depth.  Anthropogenic forcings have made a substantial contribution to this upper ocean warming.
  3. To date there is no observational evidence of a long-term trend in Atlantic Meridional  Overturning Circulation; and over the 21st century it is projected to weaken but not undergo an abrupt transition or collapse.
Ocean acidification and low-oxygen:
  1. Oceanic uptake of anthropogenic CO2 results in gradual acidification of the ocean. Since 1750 the pH of seawater has decreased by 0.1 (a 26% increase in hydrogen ion concentration).
  2. Aragonite under-saturation becomes widespread in parts of the Arctic and Southern Oceans and in some coastal upwelling systems at atmospheric CO2 levels of 500–600 ppm.  (This means that many shellfish's shells (such as mollusks) as well as coral's will dissolve in the acidity of the ocean.)
  3. Oxygen concentrations have decreased since the 1960s in the open ocean thermocline of many regions. By 2100, the oxygen content of the ocean will decrease by a few percent.  (This could cause the suffocation of many lifeforms who separate oxygen from the water when they respire underwater.)
Figure 3. A coral on a beach
Sea ice:
  1. The annual Arctic sea ice extent decreased at a rate of 3.5 to 4.1% per decade between 1979 and 2012.  The average Arctic winter sea ice thickness decreased between 1980 and 2008.
  2. Over the past three decades, Arctic summer sea ice retreat was unprecedented and Arctic sea surface temperatures were anomalously high, compared with the last 1,450 years.
  3. With global warming, further shrinking and thinning of Arctic sea ice cover is projected, and the Arctic Ocean will be nearly ice-free in September before 2050 for the high-warming scenarios.
  4. Annual Antarctic sea ice extent increased by 1.2 to 1.8 % per decade between 1979 and 2012.  The scientific understanding of this observed increase has low confidence. With global  warming, Antarctic sea ice extent and volume is expected to decrease (low confidence).
Ice sheets, glaciers, snow cover and permafrost:
  1. During periods over the past few million years that were globally warmer than present, the Greenland and West Antarctic Ice Sheets were smaller.
  2. The Antarctic and Greenland Ice Sheets have on average lost ice during the last two decades,  and the rate of loss has increased over the most recent decade to a sea-level rise equivalent of 0.6 mm/y for Greenland and 0.4 mm/yr for Antarctica.
  3. Almost all glaciers world-wide have continued to shrink since the mid-20th century.  
  4. Over the last decade, most ice was lost from glaciers in Alaska, Canadian Arctic, Greenland Ice Sheet periphery, Southern Andes, and Asian Mountains.  Current glacier extents are out of  balance with current climate, and glaciers will continue to shrink even without further warming.
  5. Snow cover extent has decreased in the Northern Hemisphere, particularly in spring.
  6. Permafrost temperatures have increased in most regions since the early 1980s: observed  warming was up to 3°C in parts of Northern Alaska and 2°C in parts of the Russian European North.
Sea level rise:
  1. During the last interglacial period, when global mean temperatures were no more than 2°C  above preindustrial values (medium confidence), maximum global mean sea level was, for  several thousand years, 5 m to 10 m with substantial contributions from Greenland and Antarctic Ice Sheets.
  2. The rate of sea level rise since the mid-19th century has been larger than the mean rate during the previous two millennia.
  3. Global mean sea level has risen at an average rate of 1.7 mm/yr from 1901 to 2010 and at a faster rate, 3.2 mm/yr, from 1993 to 2010 (this current rate is approximately 1.26 inches/decade).
  4. If global warming exceeds a certain threshold resulting in near-complete loss of the Greenland Ice Sheet over a millennium or more (confidence not assessed), global mean sea level would rise about 7 m.
  5. The magnitude of extreme high sea level events has increased since 1970. Future sea level  extremes will become more frequent beyond 2050, primarily as a result of increasing mean sea level.
Climate patterns:
  1. Models project an eastward shift of El Niño temperature and  precipitation variations over the North Pacific and North America. El Niño remains the dominant mode of inter-annual climate variability in the future, and the El Niño precipitation anomalies will intensify due to increased moisture.
  2. Monsoon onset dates become earlier or do not change and monsoon retreat dates delay,  lengthening the monsoon season. Reduced warming and decreased precipitation is projected in the eastern tropical Indian Ocean, with increased warming and precipitation in the western, influencing East Africa and Southeast Asia precipitation.
CONCLUSION

"A continuation of current trends of technological change in the absence of explicit climate change mitigation policies is not sufficient to bring about stabilization of greenhouse gases. Scenarios, which are more likely than not, to limit temperature increase to 2° C are becoming increasingly challenging." (2)

Sources Cited:

1) http://ipcc-wg2.gov/AR5/images/uploads/IPCC_WG2AR5_FactSheet.pdf
2) The IPCC's WG II 5th assessment report on climate change (March 31, 2014)
http://ipcc-wg2.gov/AR5/images/uploads/WGIIAR5-Chap1_FGDall.pdf

-Seth Commichaux

March 14, 2014

Juniper-Pinyon Forests On The Move!

In Utah, a forest has been on the move.  The Pinyon-Juniper forest has been expanding.  


A forest might seem frozen-in-time unless it's a windy day, but on other timescales trees are quite active.  Many plants move in circadian cycles or in response to sunlight.  Plants with tendrils like bean plants will reach out into their surroundings with their tendrils until they find something to grab on to, like a bean pole, at which point they will steady themselves and continue to grow upwards.  But these timescales are much too short for a forest to move.  For a forest to move it may take many, many generations.  Depending on the trees involved this may take tens, hundreds, thousands, or even tens of thousands of years.  It seems, trees might just have a different sense of time than we do.  The human perspective is limited by the fact that most of us will only live 80 years or so.  A juniper in California is believed to be over 3,000 years old and it isn't unusual for local Pinyons and Junipers to reach several hundreds of years old.  This still isn't very old compared to the age of the Earth (~4.5 billion years old).  It is hard to imagine how much change has occurred over such a long history.  Regardless, Pinyon-Juniper forests are dynamic when viewed at a speed of a hundred years per second, moving north and south, east and west, up mountains and then down again as the environment changes.

It's hard to know what the landscape was like a thousand years ago, or ten thousand, or a million, or a billion, but there is evidence that the majority of Pinyons and Junipers were living much farther south than today, only reaching as far North as Arizona, by the end of the last ice age 12,000 years ago (it's weird to think that during this time period giant sloths, wooly mammoths and saber toothed cats might've been moving amongst the same kind of Pinyon-Juniper forests that we see today.  Things change fast!).  It would be interesting to see if, back in the ice age, the Pinyons and Junipers grew to the same size or if they even looked the same as modern versions, knowing that climate and species-interactions affect the expression of genes and thus the way the trees would've looked.


Today, Pinyons and Junipers can be found from Mexico to Montana @ altitudes from 3500'-9000' in dry environments receiving ~10"-22" of precipitation a year.  Generally the forests are composed of Colorado Pinyon with one or a combination of One-Seed Juniper, Utah Juniper, Alligator Juniper, and Rocky Mountain Juniper.

As the climate changes, organisms change their ranges in response.  Also, when ecosystem composition changes or when the relationships between organisms changes, oftentimes so do the ranges of the organisms involved directly or inadvertently.  These ecosystem, compositional changes and range-shifts can happen quite fast (hundreds or thousands of years) compared to geologic time scales (millions and billions of years).  Thus, 10,000 years from now the junipers and pinyons might have moved to other areas of the continent.

More recently, meaning from 12,000 years ago until up to about 150 years ago, immigrants from Asia (the Native Americans) helped shape the range of the Pinyon-Juniper forest by cutting it down for firewood, using the pine nuts of the pinyons for a major food source as well as not controlling fires as stringently as we do today.  With the arrival of European and American explorers, pioneers and many other immigrants, tree densities initially decreased especially during the mid-nineteenth century when many Pinyons were cut down.  This was done for two reasons: For one, it undermined many Native American groups who used pine nuts in the Great Basin for a major food staple in their diet.  Secondly, the pinyons were used to make charcoal for ore-processing.  Eventually, these activities were discontinued and the Pinyon-Juniper forest began to increase its range and density.  Pinyon-Juniper forests have expanded their ranges up-slope into ponderosa pine forests and down-slope into grass and shrub communities (especially sagebrush steppe).  Much of this recent expansion can be attributed to our controlling wildfires, overgrazing grasslands and shrub-lands with domestic herds, and human-induced climate change with its corresponding increased atmospheric concentrations of carbon dioxide. 

For the most part, Pinyons and Junipers have a hard time getting their offspring to move to new areas and for their seeds to germinate without a little help.  Thus Pinyon-Juniper forest movement is actually the result of the activity of symbiosis.  For Pinyons, the Pinyon Jay is the major disperser of seeds.  It takes about 2.5 years for the Pinyon seeds to mature.  The Pinyon Jay uses the mature Pinyon pine nuts as a food source, but it also has a useful (useful for the Pinyons) habit of burying the seeds for storage.  This is especially useful for the Pinyons if the Pinyon Jay forgets about its stashes (not so useful for Pinyon Jays, but it seems one's mistake is another's fortune).  These buried seeds have the best chance of germinating and growing to adulthood.  Indeed, Pinyon seeds will rarely germinate in the wild unless they are cached by jays or other animals.  It seems that the Pinyon Jay has a habit of burying these stashes of seeds at the base of Juniper trees.  If you walk through a Pinyon-Juniper forest you often see the Pinyon trees growing right next to the Junipers, as if they were growing from the same hole.  This is because Pinyons need nurse plants to grow and Junipers tend to be nurse plants for Pinyons.  A nurse plant according to wikipedia "is one with an established canopy, beneath which germination and survival are more likely due to increased shade, soil moisture, and nutrients. Thus, the relationship between seedlings and their nurse plants is commensal. However, as the seedlings grow into established plants, they are likely to compete with their former benefactors for resources."


For Junipers, Jackrabbits and rodents (and coyotes to a lesser degree) are the main seed dispersers.  Depending on the species of Juniper, the seeds and fruits may take 1,2 or 3 years to mature.  The scarification of the seeds that occurs in the guts of the animals who eat the berries of the Juniper, as well as the excrement the seeds get balled up with before being dropped off at some new location in the environment all seem to be necessary for the successful germination and propagation of Junipers.




Many other animals use Pinyon-Juniper forests for habitat like Deer, Elk, Magpies, etc.  It is also important habitat for many winter-migrating birds.

Many farmers, ranchers, range-managers and others see the expansion of Pinyon-Juniper forests as a nuisance, even as a danger, because it is a fire hazard and crowds out grasses and shrubs for grazing of domestic animals.

Various studies show, however, that though overly dense stands of Pinyon-Juniper trees do in fact crowd out grasses and shrubs, and can pose a fire hazard, their complete elimination doesn't provide the healthiest habitat either.  Creating a patchwork, savannah-like forest seems to provide the most habitat for native animals and plants who are reliant upon these forests while also maximizing the amount of grasses and shrubs for grazing purposes.  If the trees are cut too thin or dispersed, they can't easily reproduce and replace themselves with newer generations nor can they provide adequate cover for animals and birds who use these trees to hide, rest, shelter, and nest.  Before we began to micro-manage wildfires, it seems that Pinyon-Juniper forests were evolved to withstand regular, but limited fires every 50-100 years, the forest requiring about 80-90 years to re-establish itself after such a fire.  If fires are too frequent or too large the trees can't regenerate their populations (the Utah Juniper requires about 30 years to reach sexual maturity).


After fires, the former Pinyon-Juniper forest goes through a many-years-long, ecological process of succession to get back to the forest ecosystem.  The year of or directly after the fire only perennial grasses grow.  After a few years, the perennial grasses start being joined by shrubs and after a decade or so grasses and shrubs are joined by trees.  Oftentimes, in these circumstances, sagebrush serves as a nurse plant for young Junipers who will then in turn be nurse plants for Pinyons.  As the trees get bigger they start displacing shrubs and grasses.  Thus we see that even on a shorter timescale of just a few decades that the environment is still dynamic and shape-shifting.  One species displaces another while paving the way for others to establish themselves.  Because of ecological succession, if there isn't occasionally a fire, or some other disturbance, the Pinyon-Juniper forest will eventually crowd out many other species of grasses and shrubs which in turn support a whole community of other animals and plants.  Thus for an ecosystem to be healthy and diverse, some disturbance is necessary.

As of late, we've been experiencing more frequent droughts.  With human-induced and natural climate change an on-going process, we might even see more droughts.  This is bad for Pinyons.  One study I read found that Pinyons have a 6.5 times greater mortality rate than Junipers during and following droughts.  This means that Pinyon-Juniper forests are slowly becoming Juniper-dominated forests, Junipers being more drought tolerant.  This is bad for the organisms that depend upon Pinyons like Pinyon Jays, other avian seed-dispersers, rodents, rabbits, deer, fungal and bacterial symbionts, etc. as well as the Pinyon-Juniper community which will generally be affected in unpredictable ways.



If I've conveyed anything to you, I hope it is the fact that environments are dynamic and mobile.  They change composition and direction in response to the climate and by the influences of interactions with other organisms (like humans!).  While a community, like a flock of birds, may move very fast in response to a change in weather, migrating South for the Winter for instance, other communities, like a forest, are just as sensitive to local conditions, but they move much more slowly (with the help of seed dispersers), perhaps taking hundreds or thousands of years to shift their range.  Locally, the community may change composition even faster after a disturbance such as a fire, going through a process of ecological succession. 



Life is ever-dynamic and amazingly adaptable!

-Seth Commichaux

Sources Cited:

http://www.sagestep.org/educational_resources/bibliographies/articles/2002_MillerTausch.pdf

http://link.springer.com/article/10.1007/BF02856556#page-1

http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2745.2005.01042.x/pdf

https://www4.nau.edu/direnet/publications/publications_b/files/barney_frischknecht_1974.pdf

http://pjdb.csfs.colostate.edu/Content/pdf/Gottfried_1994.pdf

http://en.wikipedia.org/wiki/Ecological_facilitation

http://en.wikipedia.org/wiki/Juniperus_osteosperma

http://en.wikipedia.org/wiki/Single-leaf_Pinyon

http://en.wikipedia.org/wiki/Pinyon-juniper_woodland