Parts of the eastern U.S. and Canada are experiencing record cold temperatures as a result of global warming.(Pixabay)

SCIENCE MATTERS: Winter weather doesn’t disprove global warming

Weather and climate aren’t the same thing

Weather and climate aren’t the same. It’s one thing for people who spend little or no time learning about global warming to confuse the two, but when those we elect to represent us don’t know the difference, we’re in trouble.

For a U.S. president to tweet about what he referred to as “Global Waming” because parts of the country are experiencing severe winter conditions displays a profound ignorance that would be embarrassing for an ordinary citizen, let alone the leader of a world power.

To understand the distinction, it’s important to know the difference between “global warming” and “climate change.”

Although the terms are often used interchangeably, there’s a subtle difference.

Current global warming refers to the overall phenomenon where global average temperatures are steadily increasing more rapidly than can be explained by natural factors. Much of the climate change we’re already seeing – from increasing extreme weather events to floods and drought to altered ocean currents – is a result of global warming.

That’s leading to a range of impacts, “including rising sea levels; shrinking mountain glaciers; accelerating ice melt in Greenland, Antarctica and the Arctic; and shifts in flower/plant blooming times,” according to NASA. That, in turn, affects everything from the food we grow and eat to water availability to human migration.

Both global warming and climate change refer to average long-term phenomena and effects, where weather refers to local changes in climate “on short timescales from minutes to hours to days to weeks,” such as “rain, snow, clouds, winds, thunderstorms, heat waves and floods,” NASA says.

So, what about those record cold temperatures in parts of the eastern U.S. and Canada?

To start, global warming is global; it doesn’t refer to one specific place. While parts of North America are experiencing record cold, places like Australia are seeing record-breaking heat. Globally, the past four years have been the hottest on record, and the warmest 20 have occurred over the past 22 years.

Several studies show global warming is causing an increasing number of cold-weather events in eastern North America. “Warm temperatures in the Arctic cause the jet stream to take these wild swings, and when it swings farther south, that causes cold air to reach farther south. These swings tend to hang around for awhile, so the weather we have in the eastern United States, whether it’s cold or warm, tends to stay with us longer,” said Jennifer Francis, research professor of marine and coastal sciences in Rutgers’ School of Environmental and Biological Sciences.

This, according to National Geographic, also means “floods last longer and droughts become more persistent.”

The study found, “severe winter weather is two to four times more likely in the eastern United States when the Arctic is abnormally warm than when the Arctic is abnormally cold.” Winters are also colder in northern Europe and Asia when the Arctic is warm.

The opposite is true in western North America, where severe winter weather is more likely “when the Arctic is colder than normal.” The effects are more pronounced when Arctic warming reaches beyond the surface, causing disruptions in the stratospheric polar vortex.

Warmer temperatures can also lead to increased precipitation, which falls as snow when temperatures drop below freezing. As a Scientific American article notes, warmer temperatures in winter 2006 prevented Lake Erie from freezing for the first time in history, which “led to increased snowfalls because more evaporating water from the lake was available for precipitation.”

Melting ice in the Arctic, Antarctic and on glaciers exposes land or sea, creating feedback loops, as dark surfaces absorb more solar heat than ice and snow, which reflect it. This accelerates warming.

So, no, a cold day where you live isn’t evidence that global warming is a “hoax.” Scientists worldwide agree: As humans continue to burn fossil fuels and destroy areas that absorb carbon dioxide, like forests and wetlands, the planet’s average temperature will keep rising, with undeniable consequences for human health and survival, as well as for the bio-diverse life on which we rely.

A study in Science Advances predicts extreme weather events could increase by 50 per cent this century if we don’t bring emissions under control. It’s time to take this seriously.

•••

David Suzuki writes for the David Suzuki Foundation.

Just Posted

Sooke’s First Nations have Iroquois links

References to the proud Iroquois race tend to make one think of… Continue reading

Famed Syrian artist displays paintings created while living in refugee camps

Farid Abdulbaki’s ‘Between Two Worlds’ exhibit will be displayed May 24-26 in Victoria

Mighty Garage Sale offers boost to Metchosin groups

Metchosin Community Association holds annual sale on May 25 and 26

Mad Hatter’s Ball offers laughs in support of Boys and Girls Club

Annual fundraising event features improv performances at McPherson Playhouse May 24

Carbon dioxide at highest levels for over 2.5 million years, expert warns of 100 years of disruption

CO2 levels rising rapidly, now higher than at any point in humanity’s history

UPDATE: B.C. pilot killed in Honduras plane crash

The crash happened in the Roatan Islands area, according to officials

Raptors beat Bucks 118-112 in 2OT thriller

Leonard has 36 points as Toronto cuts Milwaukee’s series lead to 2-1

‘Teams that win are tight’: B.C. Lions search for chemistry at training camp

The Lions added more than 50 new faces over the off-season, from coaching staff to key players

Rescue crews suspend search for Okanagan kayaker missing for three days

71-year-old Zygmunt Janiewicz was reported missing Friday

B.C. VIEWS: Reality of our plastic recycling routine exposed

Turns out dear old China wasn’t doing such a great job

B.C. ferry stops to let black bear swim past near Nanaimo

Queen of Oak Bay brakes for wildlife in Nanaimo’s Departure Bay

Mother dead, child in critical condition after carbon monoxide poisoning at Shuswap campground

The woman was found unresponsive insider her tent and the youth was taken via air ambulance to hospital

Canada’s parole officers say correctional system has reached breaking point

About half of Canada’s federal parole officers work inside penitentiaries and correctional institutions

Montreal researchers create audible hockey puck for visually impaired players

Three years ago, Gilles Ouellet came up with the idea for a puck that makes a continuous sound

Most Read