Scientists continue to learn more about climate change and how it’s impacting the world around us. Two major studies have come out in the past two days that show how the manmade global disaster is currently affecting the environment, as well as what’s to come.
Researchers at Stanford University released a study online yesterday (April 24), which was published in this week’s issue of Proceedings of the National Academy of Sciences. This first-of-its-kind study examines how climate change is impacting extreme weather events around the world.
“Our results suggest that the world isn’t quite at the point where every record hot event has a detectable human fingerprint, but we are getting close,” said Noah Diffenbaugh, the study’s lead author who is an Earth science professor at Stanford, in a press release.
In the world of climate science, scientists are careful to not irresponsibly attribute every individual weather event to climate change. They need to conduct analyses and crunch some numbers first. When the study’s 11 authors applied their testing framework to the hottest, wettest and driest events across the globe, they found that climate change increased the likeliness of the world’s “hottest events” in more than 80 percent of the cases they analyzed.
This likeliness drops to around 50 percent when looking at the “driest and wettest events.” Diffenbaugh elaborated, in the press release:
“Precipitation is inherently noisier than temperature, so we expect the signal to be less clear. One of the clearest signals that we do see is an increase in the odds of extreme dry events in the tropics. This is also where we see the biggest increase in the odds of protracted hot events – a combination that poses real risks for vulnerable communities and ecosystems.”
Past studies have looked at individual weather events to discover climate change’s influence. This study is the first to look at how it is triggering events on a macro level.
This Stanford team has, in the past, studied Arctic sea ice. They’ve found evidence of how climate change is impacting its size—and it’s on the downfall. The other study released yesterday focuses on how this sea ice could be melting faster than scientists with the United Nation’s Intergovernmental Panel on Climate Change (IPCC) originally estimated.
The Arctic Council’s Arctic Monitoring and Assessment Programme published the Snow, Water, Ice and Permafrost in the Arctic (SWIPA) assessment today (April 25). In two decades, the Arctic Ocean may see ice-free summers, according to the report. This means that more water would be entering the earth’s oceans, increasing IPCC projections for global sea-level rise.
Some areas, like northern Alaska and northeastern Russia, are experiencing extreme weather events already, according to this report. But it is not extreme cold like they’re used to; it’s extreme warm periods instead.
Much of these impacts are locked into the climate system until at least mid-century, write report authors, which includes a NASA scientist. So if the world stopped its greenhouse gas emissions tomorrow, Arctic sea ice would still continue to melt until at least 2050. But that doesn’t mean stopping emissions wouldn’t make a difference, authors clarified:
While the changes underway in the Arctic are expected to continue through at least mid-century, substantial global reductions in net greenhouse gas emissions can begin to stabilize some trends (albeit at higher levels than today) after that. Reversing trends would require reductions in atmospheric greenhouse gas concentrations.
This extreme ice melt would be expensive for the world economy, too: It could cost anywhere between $7 trillion and $90 trillion by 2100. Melting ice threatens ice roads in remote communities, restricting access to them. Some northern Arctic communities have also found it harder to find wild sources of food as the changing climate impacts animal migrating routes and hunting grounds.