Wednesday, June 03, 2020

Brace Yourself for a Wetter, Deeper Future

There won't be any Nobel Prizes for this but a report from Environment Canada says that a warmer, more humid atmosphere and increasingly heavy rains and flooding are - wait for it - linked. That's also our future, and it's our present, according to Ottawa's boffins.

Warmer temperatures due to climate change lead to wetter air, and we've seen more extreme rainfall and flooding across North America. But is there really evidence that the two are related? 
Yes, there is. 
A new study from researchers at Environment and Climate Change Canada found that climate change has made: 
- Rainfall more extreme. 
- Storms with extreme rainfall more frequent. 
"We're finding that in North America, we have seen an increase in the frequency and severity of heavy rainfall events. And this is largely due to global warming," said Megan Kirchmeier-Young, a research scientist at Environment and Climate Change Canada and lead author of the study published this week in Proceedings of the National Academy of Sciences.
I'm not sure what's new about this. Climate science has told us for years that our warmer atmosphere is now holding about 10 to 14 per cent more water vapour. That wetter and warmer air fuels severe weather events of increasing frequency, intensity and duration. It also creates "atmospheric rivers" that are known on the west coast as the "Pineapple Express" and when the jet stream stalls (as it does these days) can mean big trouble for those in its path. Ask Calgary.

Not to steal anybody's thunder but the atmospheric river phenomenon  was identified by MIT researchers in 1990.  But why stop there?


Toby said...

There is a man whose job is Okanagan Lake. Yes, you read that correctly. The lake collects water from the surrounding mountains and drains south, eventually joining the Columbia and entering the Pacific west of Portland. Simple stuff? It was back when Mother Nature was in charge. Now the drainage is regulated through a series of weirs and dams. There are many criteria including waterfront homes and fish. Too much or too little release hurts the fish while the opposites can hurt lake shore residents. Release at Penticton can be a big problem in Washington State and/or for various indigenous groups along the waterway; fortunately cooperation is good.

Now, to your point, Climate Change is making the job very much more difficult. Okanagan Lake contains so much water that release plans have to be made several months in advance. When all goes according to plan all is good; surprises are big problems. Too much warm rain in the Mountains can flood lakeside residences such that more water has to be released just when the annual salmon migration is in full swing. A sudden dry spell can mean releasing less than optimal, diverting more for irrigation, again harming fish which need cool water. It's complicated.

Climate change can be very local.

The Disaffected Lib said...

Toby, I thought the Americans were complaining that we weren't releasing enough water through the Columbia? Climate change is also creating serious flooding on the Great Lakes, especially along the Erie shoreline.

We're going to have to find some solutions and I'll bet they'll be costly.

Toby said...

During a year one is likely to hear complaints on a variety of water issues. Most of them are legitimate. Imagine having to make your plan in January and hope that Mother Nature complies in June/July/August. Adjustments are frequent and always negotiated across the border; various stakeholders are kept in the loop. Management of the Okanagan drainage system is a prime example of good cross border cooperation.

The problem that I see is one of extremes, too much or too little.

The Disaffected Lib said...

The problem of extremes is becoming widespread, Toby. That's one of the devilish aspects of the Anthropocene and climate breakdown.

I came across a report several years ago about a pastoral herder in the sub-Saharan Sahel. He had a small herd of cattle from which he made his livelihood as his family and ancestors had done for centuries. One year he got caught in a deluge. Half his herd was lost to flash floods. The following year his region was hit with severe heatwaves and drought. The rest of the herd died. He had no choice but to gather up his family, move to the slums of a nearby town and struggle to eke out a subsistence living.

I've never forgotten that.