Imbolc Valentine Moon
Two quick things from today’s lesson on the impacts of climate change. More when I’ve finished and it’s begun to sink in.
This is a helpful, hopeful slide and focuses on the idea of wedges, individual chunks that, collectively, can add up to a lot. And in the time frame required by a 3.6 degree F climate warming goal.
An analogy. Greenhouse gases are the steroids of the climate system. They change the odds.
Can you say Hurricane Sandy was caused by climate warming? Wrong way to frame the question. When you look at, say Alex Rodriguez or Mark McGuire, you don’t ask, did steroids cause that home run? You wait for the season’s statistics or perhaps more than one season and you compare them to another time in the player’s career or to other, similar players.
In the case of Hurricane Sandy we can look at certain aspects of it and say, yes, they were definitely impacted by climate warming. Here’s what wasn’t. The hurricane itself. That’s part of the natural variability of storms in the North Atlantic basin. The fact that Sandy made landfall on the night of a full moon and therefore at high tide. Bad luck.
Here’s what was. Damage from hurricanes comes from two main factors: storm surge and heavy rainfall. The storm was certainly impacted by the high tide, but sea level rise made the waves and the storm surge itself much worse. The sea is higher because water expands as the ocean heats up and because water stored in land ice like glaciers is melting faster than usual.
A warmer atmosphere, already measurable, holds more water vapor. More water vapor means there is more water available for the heavy rain events.
Both the warmer ocean and the increase in water vapor can, too, feed the overall intensity of these storms.