Tasked
with keeping a blog for 3 months for my 3rd year module in Global Environmental
Change at UCL, I came home with a world of ideas. I told my boyfriend that I'd decided to write about climate tipping points.
That's great, he said…what
are “tipping points”?
At this I paused, gave a vague description with a few
strange analogies about burning your toast, and silently vowed to find a some good
articles that would categorically sum up tipping points, for me and for my
audience.
Now, this proved much more difficult than expected. Although I knew about
tipping points in Earth’s climate system, I had never considered that they
existed elsewhere. As it turns out, ANYTHING that is in the slightest bit
dynamic has a so called “tipping point”: fashion, make-up, the economy, sport,
there’s even a Tipping Points game show in which contestants play with a giant
arcade-style coin pusher (yes I watched it . . . it’s nail-biting). What
shocked me most was that climate tipping points didn't dominate the primitive Google
search, despite potentially being one of the most daunting and difficult
factors in global climate change past, present and future.
TIPPING POINTS are thresholds beyond which dramatic changes in conditions with considerable and largely unpredictable consequences occur. It only takes a small change to make a huge difference; Lenton says “A climate ‘tipping point’ occurs when a small change in forcing triggers a strongly nonlinear response . . . qualitatively changing its future state”. They've happened before, pushing the Earth in and out of Ice Ages, but these have all been natural, caused by solar variability and a chain of events, such as melting permafrost and icesheets. This time, the Anthropocene threatens a new era of climate change, comparable with previous global mass extinctions. The editorial from Nature Climate Change Vol. 1 says “An early warning of Earth tipping points will bring us closer to staving off abrupt climate change, but a societal tipping point is needed to achieve sustainability”.
Tipping points MUST be considered by policy makers, scientists and the general public worldwide in order for the issue to be addressed and acted upon.
Image from xkcd.com, source of data for image Dyke, A. et
al, 2002. "The Laurentide and Innuitian Ice Sheets During the Last Glacial
Maximum"
No comments:
Post a Comment