In Lytton, a small village in Canada, record-breaking temperatures of 46.1C (115F), 47.9C (118F) and 49.6C (121.3F) were recorded on three consecutive days. Before this heatwave, the highest recorded temperature in the region was 45C. Similarly, Seattle and Portland in the US have seen three consecutive days of record-breaking temperatures.
The heat has driven many cities to a standstill, forcing schools, Covid-19 vaccination centres and restaurants to close, as well as prompting governments to relax social-distancing rules to allow people without air conditioning to shelter in emergency cooling centres. Nevertheless, hospitals are filling up with patients with “heat-related illnesses” and the death toll has begun to rise.
The heatwave is driven by an area of high atmospheric pressure sitting over the North American continent, which many media outlets are calling a “heat dome”. However, US president Joe Biden has joined many climate scientists and media reports in linking the extreme temperatures to climate change.
In this article, Carbon Brief summarises how the extreme heat and the role of climate change has been covered by the media.
How has the heatwave developed?
On Wednesday 23 June, US weather forecasters warned that a “historic and dangerous heatwave” would hit over the weekend, cautioning that cities in the northwest US, such as Seattle, Portland and Spokane, could see temperatures near and above 38C (100F).
As an area of high pressure began to close in on Friday 25 June, the first temperature record – a record-high minimum daily temperature in Seattle – was broken. “If you’re keeping a written list of the records that will fall, you might need a few pages by early next week,” NWS Seattle tweeted.
And, as the weekend began, media outlets were reporting that temperature records were falling in earnest. Portland, in Oregon, broke its all-time highest temperature record on Saturday, the Guardian reported, with temperatures reaching 42.2C (108F). Temperatures climbed further to 44.4C (112F) on Sunday, according to CBS News. And BBC News reported that temperatures reached 46.1C (115F) on Monday – marking the third day in a row the city set a new all-time high.
As the week progressed, other cities began reporting consecutive broken records, too. “To put it in perspective, today will likely go down in history as the hottest day ever recorded for places such as Seattle, WA and Portland, OR,” the National Weather service said on Tuesday.
According to BBC News, Seattle recorded temperatures of 38.3C (101F) on Saturday afternoon – the city’s record-high temperature for June. The Seattle Times reported that temperatures reached 40C (104F) on Sunday before rising again to 42.2C (108F) on Monday evening. This exceeds the city’s previous record of 39.4C (103F) from 2009, the Washington Post noted.
Similarly, Lytton – a small village in British Columbia, Canada – reported record-breaking temperatures on three consecutive days, according to CBC. The outlet reported that highs of 49.6C were reached on Tuesday in the village of Lytton, adding:
“Lytton, a village in the Fraser Canyon located about 260 kilometres northeast of Vancouver, also saw record-breaking highs of 47.9C on Monday and 46.6C on Sunday. Before this week, the highest temperature ever recorded in Canada was 45C in Saskatchewan in 1937.”
While Reuters reported that temperatures “fell dramatically” in some parts of the US on Tuesday, a Met Office forecast shows that temperatures are still significantly higher than the climatological average.
What are the impacts of the extreme heat?
Extreme temperatures can be deadly – especially to children, elderly people and people with underlying health conditions. The US National Weather Service issued excessive-heat warnings on Monday 28 June for much of Washington and Oregon, as well as for sections of California, Idaho and Nevada.
As temperatures rose, Reuters reported that provinces in western Canada “closed schools and universities”, so that people could stay inside. AP news added that in Seattle, the extreme heat forced a wide range of institutions to shut down:
“The heat forced schools and businesses to close to protect workers and guests, including some places like outdoor pools and ice cream shops where people seek relief from the heat. Covid-19 testing sites and mobile vaccination units were out of service as well.”
Many outlets reported on the disruption to people’s day-to-day lives, as sheltering from the heat became the main priority. “Pacific north-west cities shatter heat records again, life grinds to a halt,” read one Reuters headline.
“One Vancouver resident told AFP news agency that hotels seemed to be sold out, as people flocked there for air-conditioning, adding: ‘I’ve never seen anything like this. I hope it never becomes like this ever again.’”
ABC News added that fewer than half of the residents in Seattle have air-conditioning in their homes, as average temperatures in June are usually around 21C.
To combat the heat, many counties opened up buildings with air-conditioning – such as cinemas and shopping malls – to the public as emergency “cooling shelters”, reported Oregon Live. According to CNBC, Amazon turned part of its downtown Seattle headquarters into an emergency public cooling centre, while Reuters noted that Multnomah County, which includes Portland, opened 11 such centres – mostly in public libraries.
Despite these precautions, though, Buzzfeed News reported that, across Washington and Oregon, more than 1,100 people have been sent to hospital for “possible heat-related illness” in recent days.
And BBC News reported on Tuesday that in Vancouver alone, police had responded to more than 130 sudden deaths, in which heat was often a “contributing factor”. The outlet added:
“A doctor in a Seattle hospital told the Seattle Times the number of patients streaming in with heat stroke was comparable to the beginning of the Covid-19 pandemic.”
The extreme temperatures have also been punishing for local infrastructure. An Independent piece entitled, “Train cables melt and roads buckle in Northwest’s 46C heatwave,” noted that asphalt on the highway had “expanded and ruptured due to the hot weather”, rendering many roads unsafe for travel.
The Portland Streetcar tweeted that it was cancelling service for the day after power cables melted in the heat. Meanwhile, the Portland train service reduced the maximum speed of its services, running the announcement: “Once we hit 90F Saturday through Monday, all MAX [Metropolitan Area Express] lines will reduce speed to no more than 35mph for the rest of the day. Expect delays on all MAX lines.”
“With temperatures reaching 46C, we noted the licence plate on our vehicle surface had bubbled,” Bob Chamberlin, 56, who lives in North Vancouver, told the Times.
The Guardian reported on the disruption in Portland over the weekend:
“The hot weather had berry farmers scrambling to pick crops before they rot on the vine and fisheries managers working to keep endangered sockeye salmon safe from too-warm river water. Stores sold out of portable air conditioners and fans, some hospitals cancelled outdoor vaccination clinics, cities opened cooling centres, baseball teams cancelled or moved up weekend games, and utilities braced for possible power outages.”
Even as temperatures begin to subside, Karin Bumbaco, the assistant climatologist for the state of Washington, told the New York Times that the prolonged heat “might actually have more implications for our agriculture and potential wildfires” than the record highs.
What is a ‘heat dome’?
The extreme temperatures in western parts of the US and Canada over the past week have been driven by a phenomenon known as a “heat dome” – a large and long-lasting region of high pressure sitting in the upper atmosphere.
The Washington Post described the heat dome as a “sprawling zone of high pressure centered near the US-Canada border”, adding that its strength is “so statistically rare that it might be expected only once every several thousand years on average”.
This high-pressure zone “acts like a lid on a pot, trapping heat so that it accumulates”, wrote the New York Times. A piece in the Atlantic called it “a hot-air balloon, thwarted”. The Atlantic went on:
“In a heat dome, the [hot] air’s rise is impeded by a high-pressure system sitting on the atmosphere. When the air tries to rise, the system above nudges it back down to the surface. As the air descends, and more and more of the atmosphere’s weight settles on top of it, it becomes denser and hotter…The air can’t escape this cycle, so it just circulates up and down, getting hotter and hotter.”
Vox reported that a heat dome also “squeezes clouds away, which gives the sun an unobstructed line of sight to the ground” and allows it to warm the surface more effectively. The timing of this particular heat dome – coming just after the northern hemisphere’s summer solstice – also heightens the sun’s heating ability, the Washington Post reported:
“The high summer sun angle combined with those cloudless skies then in turn further heats the surface.”
A separate piece in the Washington Post also noted that the longest days of the year are “giving the heat dome extra time to increase temperatures”.
Writing in a “guest essay” for the New York Times, climate scientist Prof Michael Mann and climate change communicator Susan Joy Hassol pointed to the role of the jet stream in allowing the high-pressure “blocking” weather pattern to form (see Carbon Brief’s explainer on blocking for more details). They wrote:
“The heatwave afflicting the Pacific north-west is characterised by what is known as an omega block pattern, because of the shape the sharply curving jet stream makes, like the Greek letter omega (Ω). This omega curve is part of a pattern of pronounced north-south wiggles made by the jet stream as it traverses the northern hemisphere.”
According to Mann and Hassol, such jet stream patterns are “an example of a phenomenon known as wave resonance, which scientists (including one of us) have shown is increasingly favoured by the considerable warming of the Arctic”. (Links between rapid Arctic warming and extreme weather in the mid-latitudes are the subject of ongoing scientific debate – see Carbon Brief’s explainer for more.)
Yes, you are reading this correctly. Glowing white hot over +40°C (104°F) widely all along the western side of North America.
This is the animation in hourly detail. Let’s not forget about how hot the nights will be. pic.twitter.com/N2Z4Z5O1Fd
— Scott Duncan (@ScottDuncanWX) June 25, 2021
The Washington Post reported that, while heat domes are a common summertime occurrence in parts of the US south-west, the current pressure system is “striking for its incredible strength, geographic scope and persistence”.
The ongoing drought in the western US may be making the heatwave hotter as well. Dr Daniel Swain, a climate scientist at the University of California, Los Angeles, told NPR that drought and heatwaves are a “vicious cycle”. He said:
“The drought is leading to extremely low soil moisture, which is making it easier for these high-pressure systems to generate extreme heat waves because more of the sun’s energy is going into heating the atmosphere rather than evaporating nonexistent water in the soil.”
In the coming week, the western part of the heat dome will begin “gradually eroding”, according to the hazards outlook published on 28 June by the National Weather Service’s Weather Prediction Center. As the pressure system erodes, cloud cover and moist air will begin to provide relief from the heat.
What role has climate change played?
Among climate scientists, the consensus is clear – more than it is for perhaps any other type of extreme weather event – that heatwaves are being made worse by climate change. In fact, a 2016 report published by the US National Academy of Sciences on extreme weather attribution concluded:
“Heat events are arguably the extreme weather events for which attribution studies are most straightforward and have the longest history.”
The fifth assessment report of the Intergovernmental Panel on Climate Change (IPCC), published in 2013, stated that it is “very likely” that humans were contributing to the observed changes in heatwaves since 1950, and “virtually certain” that warm temperature extremes will occur more frequently as global temperatures continue to increase.
Echoing the article by Mann and Hassol in the New York Times, CNN reported that climate change may be increasing the jet stream’s propensity to get “stuck”, which can cause “severe heat, drought or wildfires”. Bloomberg reported that other record-breaking heatwaves this summer – such as those in eastern Europe and Siberia – have also been linked to the same jet stream patterns.
Met Office climate scientist Dr Nikos Christidis was quoted in a blog post as saying that a heatwave of this magnitude “would have been almost impossible” without human contributions to climate change. He added:
“[Analysis] suggests that by the end of the century these extreme temperatures are more likely than not. Human influence is estimated to have increased the likelihood of a new record several thousand times.”
Prof Friederike Otto, associate director of Oxford University’s Environmental Change Institute, was one of many scientists who tweeted about the links between the extreme heat and human-driven climate change. She wrote that the team at World Weather Attribution is “working hard” on understanding how much local factors intensified or weakened the heatwave. (For more on rapid attribution studies, see Carbon Brief’s recent guest post by Otto and others.)
Dessler told Axios:
“The mismatch between what [weather events] we are adapted for and what we actually experience can generate huge negative impacts that seem to suddenly appear out of nowhere – even though we’ve been predicting them for literally decades.”
Prof Erica Fleishman told the New York Times that “we can say extreme weather is happening more as climate changes and will continue to happen more”. Fleishman, who is the director of the Oregon Climate Change Research Institute, added that the event is “extraordinary”, but warned that it “is not likely to be the last”.
But, despite the clear connection to climate change, many local media outlets have shied away from mentioning it in their reporting. Chase Woodruff, a Colorado-based environmental policy reporter, analysed nearly 150 articles in the local news and found that just six of them had referred to climate change in any capacity.
I’m honestly stunned. That’s so abysmal. Just a total failure to perform our basic function to tell people what’s happening, what’s important and why. And this is print coverage; on TV, where most people get most of their news, I’m sure it’s worse.
— Chase Woodruff (@dcwoodruff) June 18, 2021
What has the media response been?
The record-breaking heat across Canada and the western US has received widespread national and international attention over the past few days – and many media outlets have also been keeping up a running narrative of the temperature records being broken.
The Washington Post’s Capital Weather Gang reported on Tuesday that the heatwave is “obliterating scores of long-standing records” – including a list of the 33 “all-time record highs” set since Saturday. Similarly, the New York Times said that Canada’s climate record has been “shattered” and BBC News reported that the heatwave is “sending records tumbling”.
As the heatwave progressed, reporters began to place more emphasis on the link between climate change and the extreme temperatures. On Wednesday, the Guardian reported that President Joe Biden had “joined scientists in blaming the climate crisis for [the] record-shattering heatwave”. The newspaper continues:
“‘Anybody ever believe you’d turn on the news and see it’s 116 degrees in Portland, Oregon? 116 degrees,’ Biden said in a barbed criticism of climate deniers. ‘But don’t worry – there is no global warming because it’s just a figment of our imaginations.’”
The piece adds that, according to Canadian climate scientist Dr Katherine Hayhoe, “Canada was warming twice as fast than the rest of the world and monthly higher temperatures were being broken three times more frequently than cold temperature records”.
The Washington Post’s weather editor Jason Samenow penned a piece warning that “climate change studies have warned for more than three decades that this is our future”. In the opening paragraphs, he wrote:
“Many have expressed shock about this unprecedented heat wave. Yet the writing has been on the wall for decades. Since the 1970s and 1980s, climate scientists have warned that global warming would make heat waves more frequent, long-lasting and intense. Maybe it’s only now that the reality is hitting home.”
A separate analysis piece in the Washington Post noted that “we can’t overstate how exceptional the heat is that’s blanketing the Pacific north-west”. The piece said that 55 countries have set new all-time highs just in the past decade, adding that this is “obviously a function of the world’s normal temperatures shifting higher as a result of climate change”.
A further Washington Post article stated that the event “could not have been this extreme without human-caused climate change”. It continued:
“The role of climate change has been to substantially increase the likelihood of record-breaking temperatures. Simple logic dictates a climate experiencing a background warming of several degrees will be more prone to hotter heat events.”
The Associated Press also reported that the heatwave was “worsened by human-caused climate change”. Meanwhile, Scientific American covered the heatwave under the headline, “Unprecedented heat wave in Pacific north-west driven by climate change”, and the Independent ran a piece entitled, “Once-in-a-millennium heat dome lodges over US and Canada in preview of future climate disaster”.
“The analogy that people often use is loading the dice – you have dice and they used to be fair, but now we’re loading up the sixes…But what’s actually happening is we’re hitting the point where we’ve added another side. Now we’re rolling sevens.”
Meanwhile, a Washington Post comment piece by journalist Charlie Warzel highlighted the extreme heatwave of 52C that has hit Pakistan and discussed the “existential dread” of climate change. And CBS News also called the heatwave a “once-in-a-millennium heat” event”, stating:
“Turns out, the [climate] models were correct and we should expect extreme heat waves – even unprecedented ones like this – to become more routine”.
Public officials also weighed in. Washington state governor Jay Inslee penned a piece in the Seattle Times, warning that “our recent discomfort is but the tip of the melting iceberg…What we felt this week is just the opening act in a looming global disaster.”
Reporting by the Guardian included comments from Democratic senator Maria Cantwell, who said the heat “illustrated an urgent need for the federal infrastructure package to promote clean energy, cut greenhouse gas emissions and protect people from extreme heat”.
Other pieces also warned that the failing infrastructure highlights the need to implement adaptation measures. “Adaptation, long the neglected arm of climate policy, will need to lead our efforts to address rising global temperatures”, said Atlantic staff writer Robinson Meyer.
And the Los Angeles Times ran an editorial on Monday entitled, “Record-setting heatwave shows that climate change is creating hell on Earth”, which called the heatwave a “visceral reminder that the world is not moving fast enough to curtail the use of fossil fuels and reduce carbon emissions”.
The editorial also noted that both record-breaking highs and lows of temperature have caused power outages in the US this year. It warned:
“The nation’s infrastructure is not prepared to withstand the onslaught of climate change, which can push temperatures to extremes in both directions.”
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