Thursday, August 11, 2016

That Sinking Feeling

Oops I did it again
      -Brittney Spears
Somebody must change
     - Blind Faith (Can't find my way home)
Happy Overshoot day!
       I'm not quite sure what the appropriate activity for overshoot  day might be .   Out here in Polk County, shooting guns is always an accepted means of self expression, so maybe that's it...
    The footprint folks have a number of indicators that they use to track overshoot.  One of the is of course climate.  And human emmissions continue to accelerate
"The level of carbon dioxide in the atmosphere is not just rising, it's accelerating, and another potent greenhouse gas, methane showed a big spike last year, according to the latest annual greenhouse gas index released by the National Oceanic and Atmospheric Administration.
CO2 emissions totaled between 35 and 40 billion tons in 2015, according to several agencies. Some of that is absorbed by forests and oceans, but those natural systems are being overwhelmed by the sheer volume of new CO2. As a result, the inventory shows, the average global concentration increased to 399 parts per million in 2015, a record jump of almost 3 ppm from the year before."
But possibly more worrisome is that some of what used to be natural "sinks" of CO2 may now become "sources".    One of the largest terrestrial sink is the Amazon rainforest, which is no longer a guaranteed dink, but depending on drought and fire, also is sometimes a source of CO2.  see here  
"A severe drought is again stressing trees even as it is fanning wildfires to greater intensity than during 2005 and 2010. Early satellite measures seem to indicate that something even worse may be happening — the rainforest and the lands it inhabits are now being hit so hard by a combination of drought and fire that the forest is starting to bleed carbon back. This gigantic and ancient repository of atmospheric carbon appears to have, at least over the past two months, turned into a carbon source."
Speaking of trees, a recent study indicates that the changes in the timing of snowmelt in the northern forests , is affecting their absorption as well.
"Earlier snowmelt periods associated with a warming climate may hinder subalpine forest regulation of atmospheric carbon dioxide, according to the results of a new study.
The findings, which were recently published in Geophysical Research Letters, a journal of the American Geophysical Union, predict that this shift in the timing of the snowmelt could result in a 45 percent reduction of snowmelt period forest carbon uptake by mid-century.
A separate study, also published in Geophysical Research Letters, found that earlier, slower snowmelt reduces the amount of streamflow, a phenomenon with potentially drastic consequences…"
           But the bigger picture might be the planetary limits generally .   Recently scientists have attempted to define a "safe operating space" for the earth ecosystem.   They have identified a number of key limits   see here.   One of these is biodiversity .  A recent study , see here shows that we are already bumping into that limit.
" team of researchers has concluded that biodiversity loss has become so severe and widespread that it could affect Earth’s ability to sustain human life.
The researchers examined 2.38 million records of 39,123 terrestrial species collected at 18,659 sites around the world to model the impacts on biodiversity of land use and other pressures from human activities that cause habitat loss. They then estimated down to about the one-square-kilometer level the extent to which those pressures have caused changes in local biodiversity, as well as the spatial patterns of those changes.
They found that, across nearly 60 percent of Earth’s land surface, biodiversity has declined beyond “safe” levels as defined by the planetary boundaries concept, which seeks to quantify the environmental limits within which human society can be considered sustainable.
“We estimate that land use and related pressures have already reduced local biodiversity intactness — the average proportion of natural biodiversity remaining in local ecosystems — beyond its recently proposed planetary boundary across 58.1% of the world’s land surface, where 71.4% of the human population live,” the researchers write in an article published this month in the journal Science.
In other words, more than 70 percent of the global population lives in areas where the level of biodiversity loss has been so substantial that the ability of ecosystems to support humanity is now in question."

So, where are the "leaders"?  Asleep.  Here's one attempt to get them to pay attention

Prominent organizations try for the third straight election to get candidates to answer questions about climate change and other crucial issues.
Science, especially climate science, has again gotten so little attention in the presidential campaigns that a group of more than 50 science organizations is seeking to push it into the conversation.
The group, which includes the American Association for the Advancement of Science, The National Academy of Sciences, the American Geophysical Union and Duke University, represents more than 10 million scientists and engineers nationwide. It is calling on the U.S. presidential candidates to address a set of questions related to science, engineering, technology, health and the environment, including climate change. It is also encouraging the media, the moderators that ask the debate questions and voters themselves to ask these questions of the candidates in the course of the campaign.
“Science issues are coming to influence more and more of the policy dialogues, and politicians seem to be having a hard time incorporating complex science information into their policymaking process,” said Shawn Otto, chair, which is organizing the initiative.

Labels: , , , , ,


Post a Comment

Subscribe to Post Comments [Atom]

<< Home