system
Given the following post, respond as if you're commenting on Reddit:
human
It is often stated in studies that a change in one or two degrees can have drastic effects on the climate. How does this work when the temperature fluctuates all the time?
gpt
Many reasons, but I'll try just one example. Though remember that 1 or 2 degrees is a fluctuation in **average** temperature.

If the average temperature gets 1 degree hotter, than the highest high and the lowest low will (not exactly, but let's say so) get 1 degree hotter. At the hot end, every degree is extremely important regarding effect on health, heat stroke deaths, etc. The increase in problems is sort of exponentially worse for each degree.

The difference between a 20C/68F day and a 25C/77F day is just wearing a different shirt. No problem.  The difference between a 35C/95F day and a 40C/104F day can be life and death for many people, as in the famous 2003 heat wave in Europe that killed about 10,000 people.

Really it's not quite so simple, you're more shifting a bell curve of temperatures to the hotter side, so the 35C days that used to come 3 times a year might come 10 times a year, and the 40C days that you never had before might come 3 times a year, etc. Many cities have been dealing with this already for decades due to a separate issue (urban heat island). Living in a big concrete city in summer...sucks!

This kind of thing applies to a lot of other areas. 1 or 2 degrees can make a difference. In the case of ice, if the whole world average temperature changes 2 degrees C, then there must be some regions in the Arctic where the average will go from from -1C to +1C, and ice melts when it shouldn't.  (Again, that's average, really it works out to the warm melting season being a bit longer and bit hotter over a bit larger area..though "a bit" can be millions of square km. The Earth is big.)

Also affects crops, trees, animals, weather, oceans, etc. Many things.