Hamilton’s hot weather is mirrored by escalating global average temperatures that are already closing in on the maximum increase agreed to in Paris last December by 190 countries. The city’s outdoor burning ban issued last week follows four heat warnings already this summer and the long term forecast offers little relief with no night-time temperatures below 19°C forecast until well into August.
Climate change warnings going back a decade or more predict sharp increases in plus 30°C days. The Hamilton and Niagara area have also gone through agriculturally-damaging drought conditions for much of late spring and early summer, only partly relieved Monday morning’s storm.
Global temperature averages in June broke records for the fourteenth consecutive month according to NASA and the US National Oceanic and Atmospheric Administration (NOAA). At this point, 2016 is running far ahead of any previous record year with “the highest global land and ocean temperature for January-June in the 1880-2016 record, surpassing the previous record set in 2015 by 0.20°C (0.36°F)” according to a NOAA graph released on July 20.
Those records – partly enhanced by a strong El Nino that has now ended – have pushed the global average to 1.3°C above pre-industrial levels. That’s much faster than expected last December when a majority of poorer countries – dramatically endorsed by Prime Minister Trudeau – set an objective to limit warning to 1.5°C or as little above that as possible.
Both 2014 and 2015 broke global surface heat records, and all of the ten hottest years have occurred since 1998, but most of the increases have been far less than a tenth of a degree. That changed with 2015 which surpassed the previous record by nearly twice that amount, and the 2016 numbers so far have jumped even more.
“The El Niño event, which turned up the Earth’s thermostat, has now disappeared,” warned the head of the World Meteorological Association. “Climate change, caused by heat-trapping greenhouse gases, will not. This means we face more heat waves, more extreme rainfall and potential for higher impact tropical cyclones.”
The northern hemisphere, and particularly the arctic, has been registering some of the biggest increases this year. That’s driving the most extreme northern ice cover loss yet experienced. And that drives additional warming by replacing highly reflective white surfaces with much darker land and seascapes that absorb solar radiation.
“The Arctic sea ice extent was a staggering 260,000 sq km (100,000 sq miles) below the previous record for June, set in 2010,” reports the British Guardian newspaper. “And it was 1.36m sq km (525,000 sq miles) below the 1981-2010 long-term average, according to the National Snow and Ice Data Center.”
Including the current extreme heat warning issued on July 21, advisories or warnings in Hamilton have been in place for parts or all of seventeen days since June 21. They are issued when temperatures exceed 31°C and/or a humidex of 40°C and trigger some extended hours at air-conditioned city or community facilities including swimming pools.
The warning system and the measures taken in response recognize that heat waves can cause illness and death especially for seniors and lower-income people whose health is compromised – a widely accepted fact that was recently confirmed for some European extreme heat events. Extreme heat killed thousands last year in south Asia.
Climate-related events increasingly dominate the most expensive disasters according to the Insurance Bureau of Canada. This year’s wildfire that ravaged Ft McMurray tops the list at $3.6 billion in insured losses – and far more in uninsured costs – and is nearly twice as expensive as either of the catastrophic floods in Calgary and Toronto in 2013 that rank second and fourth. The 1998 Ontario-Quebec ice storm is third and the Slave Lake fires in 2011 stand fifth.