The heat wave appeared due to an exceptionally strong
ridge centered over the area, whose strength was linked to the
effects of climate change.
Extreme event attribution found this was a 1000-year weather event, made 150 times more likely by climate change.[8] A study in
Nature Climate Change estimated that its occurrence was projected to increase rapidly with further global warming, possibly becoming a 10-year event in a climate warmed 2°C relative to pre-industrial levels.[9] The heat wave resulted in some of the highest temperatures ever recorded in the region,[10] including
the highest temperature ever measured in Canada at 49.6 °C (121.3 °F), as well as the highest temperatures in British Columbia, in the Northwest Territories, in the state of Washington as well as a tied record in Oregon. The record-high temperatures associated with the heat wave stretched from
Oregon to northern
Manitoba, and daily highs were set as far east as
Labrador and as far southwest as
Southern California.
The extreme heat sparked numerous, extensive wildfires, some reaching hundreds of square kilometers in area, leading to widespread destruction. The eponymous
Lytton wildfire destroyed the village of
Lytton, British Columbia, the day after the city set the record high temperature for Canada. Extreme heat also damaged road and rail infrastructure, forced closures of businesses, disrupted cultural events, and melted snowcaps, in some cases resulting in flooding.[11] The heat wave also caused extensive damage to agriculture across the region, resulting in a one-third decrease in yield from the worst affected crops and a loss of at least 651,000 farm animals.[12] The
National Oceanic and Atmospheric Administration (NOAA) estimated that the heatwave caused at least $8.9 billion (2021
USD) in damages in the USA.[4]
The death toll exceeded 1,400 people, with at least 808 estimated in western Canada.[2] The Chief Coroner of British Columbia reported that in the week from June 25 to July 1, 619 deaths were recorded due to heat exposure.[13] Confirmed deaths in the United States include at least 116 in
Oregon (of which 72 are in
Multnomah County, which includes
Portland),[14] at least 112 in
Washington[15] and one death in
Idaho;[16] An analysis by The New York Times suggests that around 600 excess deaths occurred the week the heat wave passed through Washington and Oregon.[3]
Meteorological history
On June 23, the United States
National Weather Service warned of an approaching heat wave in the Pacific Northwest,[17] whose origins could be traced to torrential rains in
China.[18] There, the warm, moist air rose and was eventually entrained by the
jet stream, which transported it east over cooler waters. When that air current encountered an upper-level high-pressure zone, also called a ridge, it started to significantly deform on June 25,[19] forcing to accommodate the high-pressure area south of the jet stream's meander.[20] At the same time, the Southwestern states were enduring an intense drought,[21] which had earlier allowed higher-than-average temperatures over the
Southwestern United States, leading to a
similar heat wave earlier in June.[22][23] Its remnants then moved north to the Pacific Northwest.[24] Six days later,
Environment Canada issued a heat warning for Alberta, Saskatchewan, British Columbia, Manitoba, Yukon, and Northwest Territories.[25]
These conditions made way for a massive
Rex block,[23] which is more often formed during
La Niña years.[20] In this situation, a high-pressure area stays in place for a long time and does not let cyclones pass through it, which could have cooled the region;[26] in this particular case, the high-pressure area was sandwiched between two stationary lows, which prevented the high-pressure region from moving anywhere.[29] As the Pacific Northwest, just as the Southwest, experienced severe drought conditions, the already warm air was heating more quickly than usual,[30] which intensified the ridge so strongly it caused a
heat dome.[10] Indeed, on June 27, the height at which 500
hPa air pressure was sustained (
geopotential height) was reported at 5,986 m (19,639 ft) in
Prince George, British Columbia – the highest ever recorded in the area; adjacent stations have similarly reported record-high values.[31] The
downslope winds from the
Cascades and other mountain ranges further warmed the air in the valleys.[24][28][32]
After the heat dome hovered over British Columbia and the Northwestern United States for a few days, it began to move eastward, breaking records east of the
Rocky Mountains, particularly in the northern parts of the
Prairie provinces, but bringing relief to the Pacific coast.[33][34] At this stage, the heat was kept between the
warm and
cold fronts of the low-pressure area that formed over southern
Northwest Territories and was transported eastward towards
Hudson Bay.[35] Sweltering conditions were observed as far east as
Montana,[36][37]Manitoba,[38] and
Northwest Ontario,[39]though the temperatures were not as high.[citation needed]
By July 4–5, the remnants of the heat dome crossed
Hudson Bay and, weakened somewhat by the cool waters, entered
Quebec,[40] and after that,
Labrador,[41] briefly triggering temperatures of around 30 °C (86 °F). Having beaten daily records in some localities in the
easternmost province of Canada, the
high-pressure area entered the
Atlantic Ocean on July 7, when the heat carried by the high-pressure system finally dissipated.[citation needed]
Climate change and additional factors
Climate change in Canada and
in the United States are widely considered to have worsened the heat wave's unprecedented intensity and duration.[12][42][43][44][45] According to a preliminary study, the heat wave would have been highly unlikely in the absence of anthropogenic climate change, the latter increasing the likelihood of such a heat wave at least 150-fold.[8] The work finds that either climate change made the heat wave more likely by increasing base temperatures and a combination of rare events, such as the recent drought and/or changes in the jet stream, resulted in the heat wave, or even a relatively small increase in mean global temperatures caused by climate change can pass a threshold that triggers a sharp increase in the probability of extreme heat wave phenomena.[46]
While it is yet unknown whether the frequency of these
omega blocks is due to
global heating,[10] according to the data provided by
Verisk, the Pacific Northwest is among the fastest-heating regions in the continental United States and southern Canada.[47] Moreover, the
urban heat island effect could have further exacerbated the impact in cities.[48] Based on historic data, several meteorologists noted that this phenomenon should be expected to occur only once over a thousand or several thousand years,[8][10][49] and David Sauchyn, a scientist at the
University of Regina, said that climate models had been predicting the heat wave of a similar intensity to happen in late 2020s at the earliest.[50]
Temperature records
Much of the Pacific Northwest, normally known for its temperate weather in June, received maximum temperatures 20–35 °F (11–19 °C) above normal during this heat wave.[51][52] In fact, the temperatures were so anomalous that nighttime lows were higher than the average high temperatures that this region would normally observe at this time of year.[53] Ground temperatures were also reaching extremes - in
Wenatchee, Washington, it reached 145 °F (63 °C),[54] while the pavement at an intersection in
Portland, Oregon reached 180 °F (82 °C).[55]
This heat wave, combined with other extreme weather occurrences elsewhere, yielded the hottest June on record in North America.[56] It also contributed to the hottest June ever for some localities such as
Victoria,
Abbotsford,
Kamloops and
Edmonton,[57] and in
Portland, Oregon,[58] as well as one of the hottest June mean temperatures for
Seattle[59] and
Spokane.[60] On a statewide level, June 2021 was the warmest on record in
California,
Nevada,
Arizona,
Utah and
Idaho, and second warmest for
Washington,
Oregon and
Montana, at least partly attributable to this heat wave.[61]
Canada
The highest temperatures of the heat wave were registered in British Columbia, but areas as far east as
Ontario were affected by the event. As of June 29,[update] 103 all-time heat records were set across Western Canada.[62]
Graphs are unavailable due to technical issues. There is more info on
Phabricator and on
MediaWiki.org.
The heat wave peaked in British Columbia on June 28–29. Most records of the coastal areas were made on June 28, while in the
British Columbia Interior, the highest values were largely set the following day.[citation needed]
On June 27, local records were also set in
Cultus Lake,
Lillooet,[68]Ashcroft (43.8 °C (110.8 °F))[69] and
Kamloops (44 °C (111 °F)).[70] In all, there were 59 weather stations in B.C. that set records for hottest temperatures recorded for June 27.[71] These were largely beaten in the following days (Kamloops, for instance, registered 45.8 °C (114.4 °F) on June 28 and 47.3 °C (117.1 °F) on June 29, the peak temperature recorded in a major population center in the region).[1][72][73][74]
On June 29, the temperature in
Lytton, British Columbia, hit 49.6 °C (121.3 °F), the highest temperature ever recorded in Canada,[1] although a nearby more modern station reported that the extreme was 1 °C lower.[75] The stations were temporarily isolated by the
Lytton wildfire the next day. The record occurred after consecutively setting new record highs of 46.6 °C (115.9 °F) on June 27 and 47.9 °C (118.2 °F) on June 28.[76] It is also the highest temperature ever recorded north of
45°N, the highest temperature in the U.S. or Canada recorded outside the
Desert Southwest, and higher than the absolute maximum temperatures of
Europe or
South America.[77][78]
Alberta
In Alberta, the highest heat was observed in the period from June 29 to July 1.[1][79]Banff 37.8 °C (100.0 °F),
Beaverlodge 40.5 °C (104.9 °F),
Cochrane 35.0 °C (95.0 °F),
Fort McMurray 40.3 °C (104.5 °F),
Jasper 41.2 °C (106.2 °F),
Grande Prairie 41.5 °C (106.7 °F),
Hendrickson Creek 38.3 °C (100.9 °F),
Nordegg 37.2 °C (99.0 °F),
Red Earth Creek 40.1 °C (104.2 °F) all saw the strongest heat ever measured in these communities, most after breaking all-time records of the previous day.[80]
Calgary noted 36.3 °C (97.3 °F) on June 29 and July 1, which stopped just 0.2 °C (0.4 °F) short of the highest observed temperature ever and beating the all-time records for June and July.[81][82]Edmonton also saw temperatures approach the absolute maxima – the city centre registered 37.0 °C (98.6 °F) on June 30,[83] while the
Edmonton International Airport, near
Leduc, hovered around 33 °C (91 °F) from June 29 to July 1. The heat wave had largely moved east by July 2, though, e.g.,
Fort McMurray measured its fourth daily record in a row on that date.[84]
Territories
In the
Northwest Territories, on June 28,
Nahanni Butte set a regional record at 38.1 °C (100.6 °F).[76] Two days later,
Fort Smith, just north of the Alberta border, reached 39.9 °C (103.8 °F), which beat the previous all-time territorial record, registered in the same place in 1941.[85][86][87] It was also the new highest reliably recorded temperature above
60 degrees latitude.[88]
Yukon was largely bypassed by the heat wave, but on June 28, some areas in the territory went over 30 °C (86 °F), including
Whitehorse (30.3 °C (86.5 °F)) and
Teslin (31.1 °C (88.0 °F)), both of which were daily records.[72] Teslin also beat the record for June 29, at 29.0 °C (84.2 °F).[89]
Saskatchewan
Saskatchewan's heat records were mainly concentrated in the northern parts of the province.
Stony Rapids saw the mercury reach 39.8 °C (103.6 °F) on June 30,[90] an all-time high and record temperatures were also set at
Key Lake Airport, sometimes dubbed "the cold pole of Saskatchewan",[91] and
Collins Bay Airport on July 1, both at 37.0 °C (98.6 °F),[1][92] as well as in
Uranium City (38.0 °C (100.4 °F)).[93] July highs were also observed in these settlements on the first day of the month,[94] when 26 daily records were set across the province, most in northern communities.[95]
Elsewhere, the heat arrived slightly later.
Saskatoon reached 35.4 °C (95.7 °F) on July 1[95] and beat the monthly record the following day, at 40.5 °C (104.9 °F), a tenth of degree below the all-time record.[96]La Ronge registered an all-time high with a reading of 37.9 °C (100.2 °F).[97]Regina, like most of the southern part of the province was spared the extremes reached in the northern parts, with a maximum of 35.0 °C (95.0 °F) on July 2.[98] The heat wave over Saskatchewan largely dissipated by July 3 and moved east.[99]
Manitoba
In a similar way to
Saskatchewan, the majority of heat records (including all-time highs) were noted in the northern parts of the province. A remote community of
Tadoule Lake observed 38.1 °C (100.6 °F), beating the previous all-time record by 6.2 °C (11 °F),[100] so did
Lynn Lake (38.0 °C (100.4 °F)),[92] while
Churchill, on the shore of
Hudson Bay, registered 34.1 °C (93.4 °F), the highest temperature for July.[92]
Other parts of the province did not see heat as extreme as elsewhere, though 25 daily records were set on July 3, including 35.0 °C (95.0 °F) in
Winnipeg.[101]
Ontario
Northwestern Ontario did not see all-time high records beaten, but several daily records were pushed higher: on July 3,
Thunder Bay equalled 34.3 °C (93.7 °F),
Geraldton saw 33.6 °C (92.5 °F), while the hottest temperature was in
Pickle Lake, at 35.2 °C (95.4 °F).[101][102]
Newfoundland and Labrador
Weakened by interaction with the Hudson Bay waters, and having not set any records in
Quebec, the heat wave arrived to the
mainland part of
Newfoundland and Labrador, but before dissipating in the Atlantic Ocean, it still managed to beat some daily records.
Hopedale registered 25.1 °C (77.2 °F) on July 5, while
Happy Valley-Goose Bay reached 33.2 °C (91.8 °F) the following day.[103][104]
United States
The heat wave broke numerous records by large margins. Several large cities, including
Portland,
Seattle, and
Spokane, experienced high temperatures far exceeding 100 °F (38 °C) and low temperatures higher than the area's normal daily high temperatures. The heat wave beat Washington's all-time heat record in
Hanford (120 °F (49 °C)) and tied one for Oregon (119 °F (48 °C) at two places, including at
Pelton Dam).[105] The same temperature was noted in
Peshastin in
Chelan County, Washington, where temperatures soared to 119 °F (48 °C) on June 29, slightly surpassing the previous all-time high for the state.[106][107]
Oregon
On June 26, Portland broke its previous all-time record high temperature of 107 °F (42 °C), set in July 1965 and August 1981, with a temperature of 108 °F (42 °C).[108] It topped that record again on June 27, with a temperature of 112 °F (44 °C).[109] The following day, the temperature increased further to 116 °F (47 °C).[52][110] These extremes also beat the previous record June temperature, 102 °F (39 °C) set on June 26, 2006.[51]
Salem, Oregon, reached 105 °F (41 °C) on June 26, its record high temperature for June. It then hit 113 °F (45 °C) degrees on June 27, breaking the record for the highest temperature ever recorded in that city, which was previously 108 °F (42 °C). Salem then exceeded the previous day's record temperature on June 28, with a maximum temperature of 117 °F (47 °C).[111] However, not all the regions of the mid-
Willamette Valley experienced extreme heat on June 28. Regions south of Salem, for example, did not see highs above mid-90s Fahrenheit on that day, likely due to cooler ocean air in the area.[112]
The Willamette Valley also experienced extreme overnight temperature drops (twice the size of normal fluctuations) due to cooler air coming from the ocean – Portland cooled a record 52 °F (29 °C) during the night, while Salem almost approached its all-time largest temperature swing, from 117 °F (47 °C) to 61 °F (16 °C).[113]
Washington
Between 1894, when the records in Seattle began, and June 2021, temperatures over 100 °F (38 °C) were only noted three times;[114][115] however, the Seattle-Tacoma International Airport recorded three consecutive days of temperatures over 100 °F (38 °C).[116] The temperature rose to 104 °F (40 °C) on June 27, beating the previous record of 103 °F (39 °C), only for the record to be broken again the following day by a high of 108 °F (42 °C).[117][118] All of these values broke the previous June record (96 °F (36 °C), 2017) by a large margin.[51] The suburbs farther from the coast were even hotter – a local radio station in
Maple Valley reported temperatures of 118 °F (48 °C).[119]
On June 26,
Port Angeles recorded an all-time record high of 95 °F (35 °C).[120] The
Quillayute Airport weather station, also on the
Olympic Peninsula, reported 110 °F (43 °C) on June 28, exceeding its prior record by 11 °F (6 °C).[121]
On
Mount Rainier, normally freezing temperatures reached 73 °F (23 °C) degrees above 10,000 feet (3,000 m) on June 27.[122] The heat wave was blamed for greater glacier melt on Mt. Rainier than had been seen in the state in the past 100 years.[123]
East of the Cascades, multiple locations such as Spokane measured record-breaking or -tying temperatures, beating several records over the period of a few days.[124][125][126] On June 29, Spokane,
Ephrata and
Omak all reached their all-time records, at 109 °F (43 °C), 115 °F (46 °C) and 117 °F (47 °C), respectively. These are the hottest temperatures measured since records began for those areas.[127][128][129] Extremely warm minimum temperatures were also noted: Ephrata's thermometers did not go lower than 78 °F (26 °C) on June 28[130] and 82 °F (28 °C) on June 29,[131] and all-time highest low temperature records were set at
Spokane International Airport on June 29 (77 °F (25 °C)) and June 30 (78 °F (26 °C)), during overnight hours.[132][133]
It was even hotter on and near the Oregon-Washington border. In
The Dalles, Oregon and
Dallesport, on either side of the
Columbia River, daytime high temperatures reached 118 °F (48 °C), tying the then all-time record for the state of Washington and beating the June statewide record by 5 degrees Fahrenheit.[49] The same heat was measured in
Tri-Cities on June 28–29.[134][135] The state's new official temperature record was set at 120 °F (49 °C) on June 29 in
Hanford.[136] The heat wave resulted in 128 all-time high temperature records set for individual weather stations across the state, including in Seattle.[137][138]
California
Temperature records were observed in the northern part of the state.
South Lake Tahoe observed 91 °F (33 °C) on June 28, beating the previous June record, and tied or beaten daily records for three days in a row.[139] In Redding, the temperatures soared to 114 °F (46 °C) on June 27, a daily record, while in
Siskiyou County,
Montague tied an all-time high for the county, at 109 °F (43 °C).[140]
Being largely on the margin of the
high pressure dome, Idaho did not see temperatures as extreme as elsewhere.[45] In
Lewiston, on the border with Washington, 115 °F (46 °C) was noted on June 29, beating an all-time June record and becoming the third-highest temperature in the history of recordings for the city.[142] Other localities in the
Treasure Valley to the east were expected to sustain triple-digit heat for a week (which is in and of itself unusual) and in general to tie or beat daily records.[143]Boise, for example, tied one for June 29 (105 °F (41 °C))[144] and for June 30 (104 °F (40 °C)),[145] and also recorded nine consecutive days of temperatures exceeding 100 °F (38 °C), which tied the record for such a streak.[146] Records were also beaten in the
Idaho Panhandle, with
Coeur d'Alene registering 109 °F (43 °C), which surpassed the previous highest temperature for June and equaled the all-time high for the city.[49]
Montana
Most of
Montana was placed on heat advisories, but the areas that were most affected by the heat wave were on the extreme northwest and eastern parts of the state.
Kalispell and
Missoula registered temperatures of 101 °F (38 °C) on June 29, both daily records and 1 °F (−17 °C) short of the record for June;[147]Libby succeeded in doing so, setting the plank at 109 °F (43 °C).[148] In the eastern parts of the state, several daily records were also noted:
Livingston reached 97 °F (36 °C) on June 30 and
Miles City saw 105 °F (41 °C) two days later;
Billings tied its 100 °F (38 °C) daily record on July 1 and had not fallen below 69 °F (21 °C) on July 3,[149] while
Glasgow bettered its July 1 record to 102 °F (39 °C), tied the daily high record the next day, and set the highest minimum temperatures on these days (72 °F (22 °C) on July 2).[150]
Deaths and injuries
Canada
The heat wave was the deadliest weather event in Canadian history.[153]
Over 1,000 deaths occurred due to the direct consequences of the heat wave (such as
hyperthermia). Most of the deaths occurred in
Canada – about 600 more deaths than usual were noted in
British Columbia and 66 in
Alberta.[154][155] It still unknown whether any of the excess deaths in Alberta were related to the heat wave,[clarification needed] but the Chief
Coroner of British Columbia stated that 569 casualties could be attributed to heat.[156] A later report put the heat-related death toll at 619.[13] She also said that in the prior five years, only three heat-related casualties had been registered.[157] Among the deaths reported to the provincial coroner,
Fraser and
Vancouver Coastal health authorities saw several times more deaths than usual, and the
Vancouver Island and
Interior Health health districts noted double the expected number of dead during the week from June 25 to July 1. Most of the deaths were registered on June 29.[158]
A disproportionate number of heat-related deaths during the 2021 heat wave occurred in government-funded or licensed buildings such as longterm care facilities. Of the total heat-wave-related deaths, 47 people died in community living, assisted living or long-term care facilities. Further, 62 people died from heat exposure in social housing run or funded by the provincial government. Eight individuals who lived at Vancouver Mental Health and Substance use housing died. Records show indoor air temperatures in some long-term care facilities rose to over 30°C during the heat wave.[159] Some hospitals were also unable to keep temperatures in a comfortable range for patients and staff. At least two Lower Mainland and one Northern hospital recorded indoor temperatures of over 32°C in the emergency department, while an acute care floor at Lions Gate Hospital got as hot as 38°C.[159]
In British Columbia,
E-Comm emergency dispatchers answered nearly 15,300 calls on June 26-27, which was about 55 percent above normal for the month,[160] and also deployed the ambulances 1,850 times on June 27 and 1,975 the following day - the highest number ever recorded for the province.[161][162] Delays for non-emergency calls reached up to 16 hours in extreme cases.[163] In addition to that, some ambulances were left inoperable as the emergency service was understaffed.[161] These setbacks led to hours-long delays.[164] The handling of the crisis drew criticism from the paramedics unions, which forced
Adrian Dix, the provincial healthcare minister, to change the leader of British Columbia's emergencies response management to
Jim Chu, former Vancouver's police chief,[165] and to appoint a chief ambulance officer.[166]
United States
In the United States, the death toll was lower but still in the hundreds: at least 116 deaths with confirmed heat-related causes in
Oregon (72 in Multnomah County),[167][14][168] at least 112 in
Washington[15] and one in
Idaho.[16]The New York Times analysis suggested that almost 450 excess deaths in Washington and 160 deaths in Oregon occurred during the heat wave, though it has not been demonstrated how many were related to the heat.[3] For comparison, however, Oregon had only 12 heat-related deaths 2017–2019.[169] Most of the deaths occurred among the elderly.[14][170]
On July 13, 2021,
Multnomah County, Oregon published an analysis which found that a majority of deaths occurred in households which had no air conditioning or had only fans.[171]
A surge in
9-1-1 calls and emergency department visits related to the heat saw 1,100 people were hospitalized in Oregon and Washington;[172] and almost 2,800 heat-related emergency department visits were made on July 25–30.[173] The
Washington Department of Health estimated that over 2,000 such visits occurred statewide, not including visits to
Veteran Administration or the
military hospitals.[174] In Portland, the number of calls and the response times doubled,[175] setting a record for the area.[176] On the other hand, in Oregon, while the number of heat-related visits skyrocketed, the total number of emergency visits stayed in the expected range.[177] Non-emergency municipal services were also strained—on June 26, the non-emergency health information service (
2-1-1) did not respond to 750 heat-related calls due to lack of working staff.[178]
Some deaths also occurred among those seeking cooling in the Pacific Northwest's rivers. Two swimmers in
Salem, who were trying to escape the heat, went missing in the
Willamette River,[111] another did so in Portland,[179] while in Washington, three people drowned.[180] With 30 deaths in
King County, it was the deadliest weather event in the county.[181] In fact, with 112 deaths, this became the deadliest weather event in Washington State history.[182] The total damage in Washington State was between $500 million and $1 billion.[183]
Impact
Air conditioning
The heat wave was a problem for major cities in the Northwest.
Seattle and
Portland had the lowest and third-lowest percentage of air-conditioned households among major metro areas in the United States, respectively.[184] In 2015, a
U.S. Census Bureau survey found that only 33% of Seattle homes have air conditioning (A/C) units, but that number increased to 44% in the 2019 survey, likely due to the warming trend in that area (Portland had 79% coverage, which was still below the national average).[51][185] The rate of air-conditioned households was even lower in British Columbia despite marked increases over the years –
BC Hydro estimated that only 34% of the province's residents were using these cooling appliances,[186] while a separate analysis indicated that only 21% of
Metro Vancouver's households used air conditioning in 2017 (the number was only slightly higher for Edmonton and Calgary, at 29% and 24%, respectively).[187] Authorities therefore waived restrictions related to
COVID-19 for designated
cooling shelters in Oregon,[188] Washington,[189] and British Columbia.[190]
Trying to stay cool, residents in the
Pacific Northwest and
Alberta rushed to buy A/C units, which significantly increased their prices (some double the normal), created long installation and delivery backlogs, and ultimately made them unavailable in many stores.[185][191][192][193] The pent-up demand for cooling forced electricity consumption to soar to record-high summer values.
BC Hydro reported a peak of 8,500
MW,[194]AESO registered 11,721 MW (8 MW short of an all-time high),[195]SaskPower recorded 3,547 MW,[196] while several electricity providers in Washington also logged record values.[197] It also prompted power utilities in Alberta,[195]Idaho (
Idaho Power)[198] and eastern Washington (
Avista) to formally ask to conserve energy.[199] The warning had the
Idaho State Capitol voluntarily turn off lights as a result,[200] while in the Spokane area, power outages were rolled in an attempt to prevent strain on the power grid.[197][201]
Some residents chose to shelter from the heat by booking rooms in hotels, which often ran out of air-conditioned accommodation.[202][203][204] According to
CoStar calculations, the search for cooled rooms made the hotel occupancy in British Columbia reach the highest levels since the beginning of the
COVID-19 pandemic,[205] while
Washington County, Oregon (suburbs of Portland) hotels reported occupancy levels at or exceeding +5⁄6 of total capacity on June 26–28, more than double the rate from 2020.[206]
Infrastructure
The heat wave strained and damaged the region's
infrastructure. It caused the sidewalks to buckle due to thermal expansion of concrete (57 sidewalks were damaged in Edmonton alone).[207][208][209] In
Washington and
Oregon, damage was even more severe, leading to closures of roads and other inconveniences for drivers, including on some lanes of
Interstate 5, as well as some state highways.[210][211][212][213][214] In order to prevent thermal
fatigue to
Seattle's steel drawbridges, the city announced it would hose them down with cool water.[215]
Public transportation also deteriorated during the sweltering conditions. Trains on
Link light rail and
Sounder commuter rail in Seattle operated at reduced speeds as a precaution against possible deformation of railroad tracks and
overhead lines.[216] In the
Portland metropolitan area,
TriMet suspended
MAX Light Rail and
WES Commuter Rail service for part of June 27 and all of June 28 because the cables from which the light rail cars drew electricity had sagged.[217][218] Heat-induced rail distortion, called
sun kink, slowed down the passenger service on the route of the
Amtrak Cascades.[219] Moreover, school districts in
Kamloops,
Sooke (BC),
Ephrata and
Royal City (WA) all suspended school bus services, while
Grant County, Washington limited the frequency of the buses under their management as they did not offer air conditioning or the built-in version could not cope with the heat.[220][221][222]
On June 28, 15 school districts in British Columbia's
Lower Mainland, including all districts within
Vancouver, closed due to the heat and their lack of sufficient cooling infrastructure;[223][224] many others also changed, or shortened, Tuesday schedules to avoid daytime high temperatures.[225]COVID-19 vaccination sites also endured disruption because of the weather conditions.[222][225]
Businesses and workers
Local businesses faced a choice to continue to work under oppressive heat or make a day off. Some restaurants, food stands and cafés closed, fearing excessive heat at the workplace or spoilage of solid products.[172][226][227][228] Similarly, numerous grocers were forced to shut down aisles and halt the sale of perishable goods or use plastic sheets as impromptu thermal shields, as refrigeration units failed under the load.[229] The businesses that decided to stay open often provided de facto sheltering from heat or converted parts of buildings to cooling centers, such as
Amazon.[230][231]
In a few cases, workers in California and Oregon protested the lack of air conditioning and staged local
walkouts,[232] and agricultural
trade unions had also noted increased calls to strike.[233] An SMS survey among 2,176 farmworkers in Washington (mostly in the eastern part of the state) conducted by
United Farm Workers, a labor union, reported that almost all farmers did not consider protections mandated by the state OSHA sufficient. Among the surveyed, about two-fifths reported not having had shade, just under a third not having received heat illness prevention training and a quarter of respondents had no access to cool water.[234]
After Sebastian Francisco Perez, an outdoor farm worker in
St. Paul, Oregon, died while at work, Oregon OSHA faced calls to enforce safety rules for dealing with the heat wave, which had been first drafted in May. In response, Oregon's governor,
Kate Brown, directed the agency to enforce the safety regulations for 180 days pending permanent implementation.[235][236] In Washington state, the heat wave prompted state agencies to roll out additional protections.[237][238]The Washington Post reported that the federal
Occupational Safety and Health Administration was also considering a set of heat-related safety rules, whose implementation was said to be a "top priority" for the
Biden administration.[239]
Culture and sports
Sports events were disrupted by the heat wave. In
Eugene, where the qualifiers for the
2020 Summer Olympics were held, the heat caused evacuation of the stadium in the afternoon and postponement of some events to the evening hours, as the temperature of the stadium's track exceeded 150 °F (66 °C).[240][241] It also caused an athlete to withdraw from the race.[241]
Among other disruptions, a public swimming pool in Seattle's
Rainier Beach neighborhood was closed due to dangerously high deck temperatures,[242][243] so was a senior's center in
Rathdrum, Idaho[244] and a golf course on
Vancouver Island.[245] Some local concerts were also moved to avoid the heat.[246][247]
Farms have experienced serious losses, as the heat wave baked the fruits and berries or otherwise destroyed the crop and the drought conditions worsened.
10 million pounds of fruit per day were being harvested in the Pacific Northwest at the time the heat wave struck.[248] Farmers in
Eastern Washington, facing a loss of the
cherry and blueberry crop, sent workers into orchards at night to avoid the heat in the day.[249][250][251][252] The British Columbia provincial fruit growers association estimated that 50 to 70 percent of the cherry crop was damaged, effectively "cooked" in the orchards.[253] Raspberry and blackberry farms in the
Lower Mainland, Oregon and Washington have also endured losses.[254][255][256][257] In
Whatcom County, Washington, which produces four-fifths of raspberries in the United States, estimates varied from quarter to half of the harvest;[258][259] elsewhere, they went as high as 80-90%.[254][260] Lettuce producers in the
Okanagan Valley were also reported to be struggling with spoilt crops,[261] so were those who grew Christmas trees[262] and apples.[263] In contrast, grapevines in Oregon and Washington did not seem to have sustained much damage,[5] and corn in
Skagit County, Washington was growing much ahead of schedule.[263]
Farmers in the United States have also seen reduced yields of soft wheat, which additionally saw the quality deteriorate (68% of wheat harvest in the Pacific Northwest was estimated by the
USDA to be of poor or very poor condition).[5] In the
Prairie provinces, an infestation of
grasshoppers is threatening
cash crops[264] and farmers were reported to be struggling with feeding
cattle as hay and forage was found to be in short supply.[265] Saskatchewan has therefore extended additional drought support for farmers.[266] In Alberta, lack of rain and excessive heat saw some grain plants catch fire, which has put the harvest in jeopardy.[256]Beaumont, Alberta issued a mandatory ban on non-essential water usage, citing
drought conditions.[195] Further east,
St. Laurent and
Armstrong, Manitoba declared a "state of agricultural disaster" as the heat wave worsened the drought in the region, whose water reserves were already depleted.[267]
The heat event sparked significant fires across the
West Coast and
Western Canada.[62] One of the first fires to have struck the region was the
Lava Fire, burning west of
Mount Shasta, California, caused by a lightning strike on June 25,[268][269] and which eventually burned around 26,300 acres (106 km2) on the west slope of one of the highest peaks in the state.[270] Some of the largest fires, such as the
Beckwourth Complex Fire, grew over 100,000 acres (405 km2). Strong winds, which were causing
fire tornadoes in some places,[271] and dry vegetation hampered efforts to contain the fires. This led to road closures, such as the
U.S. Route 97 and the
North Cascades Highway,[272][273][274] suspension of airport operations in
Redmond, Oregon, and evacuation of settlements adjacent to the fires.[269][275][276] The winds were so strong that residents of
Medford, Oregon,
c. 80 mi (130 km) north of the fires, reported having seen ash falling from the sky.[277]
Among the most known fires was the one that burst in the evening of June 30 in British Columbia. Then, Lytton, the settlement that had been beating national heat records in the previous days, along with several
First Nations reserves, were ordered to be evacuated as a likely human-caused[278]fire was approaching to the village, where it later did widespread destruction to the buildings.[279][88][280] A local
MP,
Brad Vis, estimated damage to the settlement at 90%,[281] while a local resident said that only "four or five houses, the post office and the church were still standing".[282] The fire damaged roads, telecommunication and power facilities as well as the
railway that comes through the settlement;[88][283][284] two people died while hiding from the flames.[285] The fire in the settlement forced the closure of a section of
British Columbia Highway 1, part of
Trans-Canada Highway, as well as
Highway 12, which ends in Lytton.[286][281] In total, 300 fires were ravaging the province as of July 13,[287] and the
wildfire season destroyed around 2,230 km2 (860 sq mi) of forests by July 15.[288]Pyrocumulonimbus clouds formed due to such extensive burning, producing several hundred thousand lightning strikes in one day and further complicating efforts to contain fires.[289]
Despite deployment of more than 9,000 firefighters in the United States to extinguish them by July 1[290] and more than 17,000 by mid-July,[291] the size and number of the fires grew. Almost 1,000,000 acres (4,050 km2) of forest were consumed by large wildfires, and more than 2,250,000 acres (9,110 km2) were burnt in the United States as of July 15.[291] The intensity of the fires moved the US fire preparedness alert level to 5 (highest) by July 14, which was an early start of the wildfire season.[292] In addition to that, Governors
Kate Brown of Oregon,
Jay Inslee of Washington and
Brad Little of Idaho declared states of emergency due to the extreme risk of wildfires.[293][294][295] The
Canadian army officials set up a coordination center in
Edmonton in order to assist wildfire actions in British Columbia, which would be directed until July 19.[282] Higher-than-average burning also appeared in Albertan, Saskatchewan and Manitoba forests.[296][297][298][299]
As the extreme heat and dry conditions persisted, scientists, firefighters and various politicians urged residents not to use fireworks during
Independence Day celebrations in the Western United States[300] and on
Canada Day in Alberta.[301] In addition to that, Washington and British Columbia enacted state-/provincewide bans on most open fires, and Washington authorities also issuing a total fire ban in state parks.[302][303] Idaho and Manitoba were using more regionalized approaches, though the latter suspended all burning permits provincewide.[299][304]
As of September 14, 2021, the National Interagency Fire Center (NIFC) reported that 44,647 wildfires in the United States had burned 5.6 million acres of land.[305] Similarly, the Canadian Interagency Forest Fire Centre (CIFFC) announced that 6,317 wildfires burned 10.34 million acres.[306] Initially, the NIFC declared that the United States and Canada had a preparedness level of 5, meaning it had the potential to exhaust national firefighting resources.[307] Due to the earliness and severity of the wildfire season, the United States and Canada were unable to provide each other with aid as in previous years.[308] However, by September 20, 2021, the national preparedness level was reduced to 4 and 1 for the United States and Canada, respectively.[309]
In April 2021, the North American wildfire season was predicted to be severe due to record drought conditions and high spring temperatures in the West.[310] In May, more than 75% of the western United States experienced drought conditions, with 21% of these conditions being deemed as "exceptional drought", which is the most extreme level of drought.[311] These extreme conditions result in a lack of moisture on the ground that is imperative for combating wildfires.[312] In Arizona, there were 311 early wildfires in the first four months of the year, compared to 127 in the same period in 2020.[313]
In July 2021, haze from West Coast fires was affecting East Coast cities,[314][315] and particulate pollution caused unhealthy air quality in New Hampshire.[316]
In Montana, evacuation orders had displaced around 600 people by early August.[317]
Extreme temperatures were also noted for mountain regions, which accelerated
the melting of glaciers. Extensive melting occurred in the snowcaps of
Banff National Park, which a
glaciologist estimated that the Albertan snow from the mountains melted three times faster than usual.[318] On
Mount Rainier, the heat wave caused the mass of the snow cap to shrink by 30%, and
Washington's glaciers in general have come through what glaciologists say to be the strongest melting episode in 100 years. Additionally, the increased melting of glaciers caused high amounts of runoff to be present within some rivers.[319] The unexpected snowmelt blocked some high mountain roads in
Whatcom County, Washington[320] and rendered three hiking trails in
British Columbia impassable.[321] More importantly, it caused
flash flooding down the creeks and rivers, which the glaciers feed. This triggered i.a. a week-long evacuation order in the
Pemberton Valley[322] extreme water rises were also noted in
Squamish,[323] and flood alerts were issued for other parts of British Columbia.[324]Soot from wildfires (→
2021 British Columbia wildfires) is further expected to diminish the mass of ice.[325]
Wildlife and fisheries
As the surrounding air was extremely hot, water temperatures rose, which proved to be a hazard for aquatic wildlife. On the Pacific shore, temperatures in the intertidal zone reached up to 122 °F (50 °C) and more than a billion seashore animals, like
clams,
barnacles and
oysters, died as a result of heat wave, impacting water quality.[326][327] The deaths also impacted seafood producers, who faced losses of produce as it baked in the heatwave and started rotting.[328][329][330] Inland, the population of
sockeye salmon in Idaho rivers was preventatively caught out of water as increasing temperatures made it prone to disease;[29] some salmon was also transported to cooler waters in the
Columbia River.[262] Fish kill, however, was not prevented in Albertan aquifers and appeared earlier than expected.[331]
The heat wave caused an increase in
vibrio bacteria levels in oysters in the Pacific Northwest, causing a record number of people to be sickened from
vibriosis, an intestinal disease caused by the bacteria. The Washington State Department of Health urged people not to eat raw oysters and other shellfish from the region due to the risk of bacterial contamination.[332][333]
On the land, trees in
Metro Vancouver dried up and started shedding leaves;[334] the same happened to the fir canopy in Oregon on the side where the trees faced the sun,[335] and reportedly also in Lytton just before the wildfire swept through the community.[336] Birds have also come through distress - in Seattle, nearly a hundred juvenile
terns, whose nests were on top of an industrial building, died when they plunged to the pavement below, presumably trying to escape the heat - those that survived were treated for burns.[337] Scores of British Columbian
raptors, apart from heat exhaustion, were suffering from dehydration and starvation.[338]
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