In 50 years, Puget Sound residents will see mostly the same plants and animals they see today, but some changes can be expected. Our favorite species may disappear from places where they are now common.
Climate change is expected to bring higher temperatures, shifts in precipitation patterns, rising sea levels and ocean acidification. Some species will no doubt cope where they are. Some will not. Some could move to more hospitable locales, perhaps farther north or to higher elevations in the mountains.
“There are going to be some winners and some losers,” research biologist Correigh Greene told me. His comment seemed to sum up the situation nicely, and I used this quote in the final installment of a three-part series I wrote for the Puget Sound Institute and the Encyclopedia of Puget Sound.
All three climate stories are largely based on a new report from the Climate Impacts Group at the University of Washington called “State of Knowledge: Climate Change in Puget Sound.”
What stands out in my mind is how Puget Sound’s food web could be disrupted in unexpected ways. For example, tiny shelled organisms — key prey for many fish species — are already dying because they cannot form healthy shells. And that’s just one effect of ocean acidification.
The observations mentioned in my story and in the report itself come from a variety of experts who understand the needs of various species — from those that live in the water to those dependent on snow in the mountains. What will actually happen on the ground depends on many variables — from the buildup of greenhouse gases to changing trends such as El Nino.
As things are going, it appears that this year will be the warmest on record. The global average surface temperature is expected to reach the symbolic milestone of 1 degree Celsius above the pre-industrial era, according to the World Meteorological Organization. The years 2011 through 2015 have been the warmest five-year period on record, with many extreme weather events influenced by climate change, according to a five-year analysis by WMO.
The new report from the Climate Impacts Group discusses various scenarios based on total emissions of greenhouse gases. High scenarios presume that emissions will continue as they are now. Low scenarios presume that people will dramatically reduce emissions. What will actually happen is unpredictable at this time.
Greenhouse gas emissions are used to predict carbon dioxide concentrations in the atmosphere, ultimately pushing up the average global temperature. The first graph below shows the range of annual emissions (in gigatons of carbon) depicted by the various scenarios. The next graph shows how the emissions translate into atmospheric concentration. One can take any of the scenarios and see how the levels translate into temperatures at the end of the century. For a more complete explanation, go to page 19 of the report, where these graphs can be found.