Author: Milan

Wet bulb temperatures and human death

The many human impacts of climate change are complex and often indirect, like how warmer winters in the mountains affect downstream agriculture. The most direct possible effects — however — have been on display in the brutal heat waves on the west coast, as well as elsewhere in the world.

CNN recently published an editorial by Ban Ki-moon and Patrick Verkooijen on the most direct imaginable way in which increased global temperatures can bring harm upon people:

Sweltering temperatures have become the norm in Jacobabad, a town of around 200,000 inhabitants in Pakistan’s Indus Valley that has become one of the hottest places on earth. Temperatures can top 126 degrees Fahrenheit and air conditioning is scarce, leaving the streets deserted and forcing farmers to till their fields at night.

The city, along with Ras Al Khaimah in the United Arab Emirates, has temporarily crossed the threshold beyond which the human body cannot sweat enough to cool itself down. A “wet bulb” temperature of 35 degrees Celsius (95 degrees Fahrenheit) — which factors both heat and relative humidity — can be fatal after a few hours, even assuming ideal conditions such as unlimited drinking water, inactivity or shade. In practice, the bar for this wet bulb temperature, which is measured by covering a thermometer with a wet cloth, is much lower — as shown by the deadly heat waves in Europe in 2003 that are estimated to have claimed 70,000 lives.

Our most basic biological function and a prerequisite and definition of life is the ability to maintain stable conditions inside the body compatible with the needs of our physiology and biochemistry; homeostasis is the term for maintaining internal conditions, and if you don’t have it you’re literally dead.

We’re already artificially coping with places which are literally unliveable without air conditioning, from scorching cities around the Persian Gulf to Phoenix and Las Vegas, which are also profoundly threatened by the loss of winter snowpack and lost river volume and reliability.

Networked citizen science ecology

Promoted by a recent Economist article on biodiversity and Alie Ward’s podcast on foresting ecology, I am trying out the iNaturalist app.

My outdoor pursuits mostly consist of walking at a steady pace for exercise, so plant and wildlife observations aren’t my priority. Nonetheless, it’s neat to be able to take a break anywhere in the city and use the map in the app to see what people have documented in the neighbourhood.

Canada submits new 2030 climate target

Canada is now promising the UN that it will cut greenhouse gas emissions to 40–45% below 2005 levels by 2030.

The government says emissions are already set to fall from 729 million tonnes (MT) in 2018 (the last year with final figures) to 468 MT by 2030.

Canada’s choice of a 2005 baseline sets it apart from the global standard of setting targets compared to 1990 emissions as required by the UNFCCC reporting guidelines, effectively forgiving 15 years in which bitumen sands output and Canadian GHG pollution rose substantially. Canada’s emissions rose from 600 MT to 747 MT between 1990 and 2005.

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