Evidence for Climate Change
Global surface average temperatures have been rising for decades. That’s beyond weather change, it’s climate change. One of the difficulties of understanding the magnitude of climate change is that the differences we’ve seen so far are relatively small. What we see around us is weather. But weather is to climate like the changing surf is to the tide. Standing on the shore we see one wave higher than the next, but then several smaller and then another higher, and so on. Is the tide coming in or going out?
So with weather and climate. We see one hot year, then a cooler one, then another hot one and so on. Is the climate warming or not? To see the magnitude of climate change we need to look at the long term, not the short. And the long term trends are irrefutable. The climate is warming.
What is some key evidence for climate change?
- Global average temperature is rising.
- Greenhouse gas concentrations are higher than they’ve been in 800,000 years, which is much longer than homo sapiens (we) have existed.
- Glaciers and sea ice are melting and sea level rise is accelerating.
- Animals and crops are moving to cooler climates.
See also an excellent compilation of evidence by the US National Academy of Science and the Royal Society.