2017 was the second-hottest year on record according to Nasa data, and was the hottest year without the short-term warming influence of an El Niño event:
In fact, 2017 was the hottest year without an El Niño by a wide margin – a whopping 0.17°C hotter than 2014, which previously held that record. Remarkably, 2017 was also hotter than 2015, which at the time was by far the hottest year on record thanks in part to a strong El Niño event that year.
For comparison, the neutral El Niño conditions and the level of solar activity in 1972 were quite similar to those in 2017. 45 years later, the latter was 0.9°C hotter than the former. For each type of year – La Niña, El Niño, and neutral – the global surface warming trend between 1964 and 2017 is 0.17–0.18°C per decade, which is consistent with climate model predictions.
1964–2017 global surface temperature data from Nasa, divided into El Niño (red), La Niña (blue), and neutral (black) years, with linear trends added. Illustration: Dana Nuccitelli
Those early years were the height of the denier frenzy about the mythical global warming ‘hiatus.’ At the time, John Abraham and I frequently wrote pieces pointing out that while various factors were temporarily dampening global surface warming, the oceans (which absorb over 90% of the excess heat from the increased greenhouse effect) continued warming rapidly.
Climate scientists predicted this rapid temperature rise
It was only a matter of time until short-term effects stopped holding back the rise of Earth’s surface temperatures. That’s now happened, and as a result we’re seeing unleashed global warming causing record temperatures year after year. In fact, in February 2014 I wrote about a study that predicted this would happen:
the [ocean] heat uptake is by no means permanent: when the trade wind strength returns to normal - as it inevitably will - our research suggests heat will quickly accumulate in the atmosphere. So global temperatures look set to rise rapidly out of the hiatus, returning to the levels projected within as little as a decade.
Temperatures have in fact risen so quickly, it appears to have taken just a few years for that prediction to come true and for the denier focus on the short-term surface warming slowdown to look quite foolish.
2017 – a year of climate denial
Speaking of climate denial, on the 362nd day of the hottest year on record without an El Niño, the US president tweeted this:
Billion-dollar weather and climate disasters in the US in 2017. Illustration: National Oceanic and Atmospheric Administration
These extreme weather events are expensive, and they’re a mere taste of what’s to come. Until we manage to cut global carbon pollution, temperatures will continue to rise and climate change consequences will become more severe. While it broke many of today’s records, 2017 is just a taste of what’s to come.
Last week’s record-setting heat in the Pacific Northwest and current triple-digit temperatures in Arizona are the latest reminders that climate change is heating up the Earth. This trend is a serious threat to cities, which are warming at higher rates than other parts of the planet.
A recent multi-country analysis found that from 1950 through 2015, 27 percent of cities and 65 percent of urban populations experienced greater warming than the planetary average of 1 degree Fahrenheit. About 60 percent of the world’s city dwellers experienced warming twice as great as the rest of the world.
One or two degrees may not seem like much, but for especially vulnerable groups like the elderly, the sick, the poor, pregnant women and infants, it may be enough to tip the scales. In a time of global warming and intensifying summer heat waves, life in cities is becoming more perilous. As I found in a recent study, this is especially true for marginalized groups such as minorities and the poor.
Deadly overheating
Studies of the urban heat island effect date to the 1830s, when British chemist Luke Howard demonstrated that temperatures in London were consistently warmer than those at sites outside the city. Heat islands develop when a large portion of the natural land cover in an area is replaced by built surfaces like roads and buildings. These structures trap incoming solar radiation during the daylight hours and release it at night.
Cities, in effect, have their own climates. During recent decades, the largest urban heat islands in the U.S. experienced warming at twice the level of the “cooler sea” of smaller urban and nonurban areas. As the human population continues to urbanize and consume more fossil fuel, the health, social and economic impacts of summer urban overheating loom as major threats to the well-being of city dwellers worldwide.
Human bodies are not designed to handle heat above certain levels, especially if there is no cooling respite at night. The human body core, which includes the brain, lungs and other organs, functions only within a narrow temperature range. A core body temperature of 103°F or above can be a sign of heat stroke.
How bad might it get? One recent study estimates that about 30 percent of the world’s population currently is exposed to deadly heat episodes for 20 days or more each year. By 2100, this figure is projected to climb as high as 74 percent unless there are reductions in greenhouse gas emissions. New York City could be subjected to 50 such days per year, while southern cities like Orlando, New Orleans and Houston could see 100 deadly hot days each year. Even with reductions, the study estimates that by the end of the century, half of the people on Earth will likely face at least 20 days each year when extreme heat can kill.
Cutting-edge climate science already can robustly attribute specific levels of human mortality caused by climate change during extreme weather events. During the lethal summer heat wave in Europe in 2003, for example, when tens of thousands of people perished, particularly the elderly, calculations show that anthropogenic climate change increased the risk of heat-related mortality in central Paris by 70 percent and in greater London by 20 percent.
Protecting minorities and the poor
No matter what we do to slow greenhouse gas production, the heating of cities will continue for decades because of the amount of carbon already released into the atmosphere. The question is what can be done to diminish impacts of urban heating, including educating people about the issues and involving them in planning for the future.
Of particular concern is the fact that for many reasons, low-income ethnic minorities are excluded from initiatives to adapt to climate change. For example, they have limited material resources, have historically been socially and politically marginalized and face barriers that hinder them from participating in decision-making forums.
To address these issues, I conducted a qualitative study with several of my students, building on my 30 years of involvement in health-related research. We interviewed a sample of low-income and increasingly vulnerable Latinos about their climate change-related knowledge, attitudes and behaviors.
Participants were recruited from the client list of a community service agency in Hartford, Connecticut and included both men and women. Like New England generally, the city they live in faces significantly greater warming over the next decade than other parts of the United States.
Heat index readings combine temperature and relative humidity. High humidity makes heat more dangerous because it reduces the cooling impact of sweating. (image: National Weather Service)Aware but powerless
We found that our study participants were generally aware of climate change. Further, they could tell us about the various ways it was already affecting their lives, citing confusing weather patterns and drastically hot summer days. As one participant commented,
“Global warming is going to get worse than what it already is. It could get worse and become stronger heat, [and] wear down the polar glaciers and all that. Like now the heat is strong [and] maybe it will change to be [even] hotter… This temperature right now, I feel suffocated. Like it’s too strong. It’s different [than] previous years.”
Nonetheless, our participants often lacked clear knowledge about the nature of climate change, what drives it, how climate change differs from other forms of urban pollution or how people can prepare themselves for limiting its harmful effects. Their strongest concerns were about how oppressive summer heat waves would make their children sick and their own ability to cope with ever-higher temperatures and longer heat spells as they grew older. Some described feeling powerless given the scale of the social and climatic forces aligned against them.
Participants reported feeling excluded from local preparatory efforts to mitigate adverse impacts. They said they received no information about preparing for climate change, except for notices that the city had started opening up a few cooling stations in the lobbies of air-conditioned buildings during the summer. Still, they expressed a strong desire to learn more and to better understand how to protect themselves and their children in an ever-hotter world.
Planning should involve everyone
Some observers have asserted that low-income groups are too focused on everyday coping with multiple socioeconomic challenges to be concerned about climate change. On the contrary, we found that people were both anxious about global warming and eager to become climate-savvy and make informed decisions about responding to the looming threat of urban heating. They were not confused by climate change deniers’ intense disinformation campaigns and wanted skills and technologies that would allow them to reduce their vulnerability.
Our findings demonstrate that there is an urgent need for climate change planning efforts that give all urban residents a voice. They also show the importance of conducting research with communities that will be most affected by climate change’s adverse impacts on city dwellers.
From Phoenix to Boise, high temperature records fell like dominoes last weekend as an impressive heat wave engulfed the western U.S., helping to fuel several wildfires.
While heat waves are a regular part of summer weather, the steady warming of the planet means those heat waves are getting ever hotter, making record heat more and more likely.
The heat came courtesy of a ridge of high pressure that moved in over the West, with the peak temperatures, including several records, occurring on Friday and Saturday last week:
Las Vegas hit 116°F on Friday, besting the record set in 1989 of 114°F. The city had a record-long streak of 23 days with highs above 105°F.
Los Angeles broke a record that had stood for 131 years, with the temperature downtown hitting 98°F (the old record was 95°F).
Temperatures in Phoenix soared to 118°F on Friday, besting the old record of 115°F set in 1905, and marking the third day of 2017 where temperatures were at or above that level, the second most on record.
In Salt Lake City, the temperature reached a record 104°F on Saturday. The city had three record highs in just four days last week.
The Boise airport also saw 104°F on Saturday, besting the record of 103°F set in 1968.
Daytime highs weren’t the only concern, as overnight lows stayed downright hot in some places, particularly in the Phoenix area. The temperature from Friday night to Saturday morning only reached as low as 95°F in Scottsdale, a record. (It was still 106°F at 1 a.m. that night.)
Overnight lows on Saturday morning in the Phoenix area stayed in the 90s. (credit: NOAA)
The heat and accompanying dry conditions can also set the stage for wildfires, as was the case during this heat wave, which saw several wildfires ignited and grow across the region.
The Whittier fire, which started on Saturday in the Santa Ynez Mountains in Southern California, has burned more than 10,000 acres, while the nearby Alamo fire has burned nearly 29,000 acres and forced several thousand people to evacuate.
The ridge of high pressure is moving eastward this week, bringing sweltering temperatures — and the threat of wildfires — to the northern and central Plains before shifting back to bake the West again at the end of the week.
At that point it could strengthen, meteorologist Guy Walton wrote on his blog, keeping the West good and toasty for the next week or two.
Extreme heat is one of the hallmarks of global warming; as the average temperature of the planet rises, record heat becomes much more likely than record cold. And cities in the Southwest — where most of the region’s population lives — are some of the fastest-warming in the country.
While no formal attribution study has been conducted to see how much more likely a heat wave like this has become with warming, a recent study found that heat records were made both more likely and more severe for about 80 percent of the area of the globe that had good enough observational data.
With temperatures continuing to rise — and no substantial effort yet to curtail the greenhouse gas emissions driving that rise — the world at large stands to see more such extreme heat in the future. Another recent study found that half of the world’s population could be exposed to heat that reaches deadly levels by the end of the century even with the most stringent reductions in greenhouse gases.
These kind of heat waves pose threats to public health, local economies and infrastructure. The increased use of air conditioning can tax the electric grid, while the heat can damage crops and curtail outdoor activities, such as construction. During a June heat wave, planes in Phoenix couldn’t take off because higher temperatures lead to thinner air, making it more difficult for planes to get off the ground.
And searing heat can be deadly to already vulnerable populations, such as the elderly, small children and those suffering from illnesses. High overnight temperatures are a particular concern when it comes to the health effects of heat waves, because they prevent the body from cooling down and recovering from the heat of the day.
Nighttime lows have risen across the Southwest since 1970, ranging from an increase of 1.7°F on average in California to 3°F in New Mexico.
And even if the governments of the world act on promises they made in 2015 and drastically reduce greenhouse gas emissions, almost one in two could face the risk of sickness and death by intolerable heat.
That is because, as the temperatures rise, heat and humidity begin to challenge human physiology. Humans are adapted to body temperatures of around 37°C. If humidity—the levels of water vapour in the air—go up with the thermometer, then people caught in a zone of extreme heat cannot adjust body temperatures by perspiration.
And with every 1°C rise in temperatures, the capacity of the air to hold moisture goes up by 7 percent. People with no access to air conditioning or a cool breeze become at high risk.
It happened in Europe in 2003, when an estimated 70,000 died. A heat wave in Moscow in 2010 killed around 10,000. And researchers warned years ago that under global warming predictions, more such extremes of heat would become inevitable by 2020.
“We are running out of choices for the future,” said Camilo Mora, a geographer at the University of Hawaii at Manoa, who led the study.
“For heat waves, our options are now between bad or terrible. Many people around the world are already paying the ultimate price of heat waves, and while models suggest that this is likely to continue, it could be much worse if emissions are not considerably reduced.
“The human body can only function within a narrow range of core body temperatures around 37°C. Heat waves pose a considerable risk to human life because hot weather, aggravated with high humidity, can raise body temperature, leading to life-threatening conditions.”
Dr. Mora and colleagues warned years ago that by 2016 climate would change inexorably in at least some regions of the globe. More recently he and colleagues calculated that the relentless increase in carbon dioxide levels in the atmosphere could limit the growing season and pose a threat to world food security. History has yet to deliver a verdict on either prediction.
Uninhabitable
But the warning about heat waves starts from facts already available. One scientific group has calculated the humidity and temperature hazards and predicted that at least one climate zone—the Gulf between Iran and the Arabian Peninsula—could become murderously hot by the century’s end.
Dr. Mora and colleagues in the U.S. and Britain report in Nature Climate Change that they found evidence on a global scale. They began with 30,000 relevant publications and identified 911 scientific papers with data on 1,949 case studies of cities or regions where deaths were associated with high temperatures.
From this mass of information they found 783 lethal heat waves in 164 cities across 36 countries, with most cases recorded in developed countries at mid-latitudes since 1980: in cities such as New York, Washington, Los Angeles, Chicago, Toronto, London, Beijing, Tokyo, Sydney and São Paulo.
Risk mapped
From this data, they found a common threshold at which temperatures and humidities became lethal: that is, as relative humidity climbed, even lower temperatures could kill. And then they devised a world map of those cities and regions most at risk.
Right now, one human in three lives in a climate zone in which death by extreme heat is or could be possible. The area in which such conditions are liable to happen on at least 20 days a year is predicted to grow.
By 2100 New York could have around 50 days in which conditions could be potentially lethal. In Sydney, Australia the number of such deadly days could be 20, for Los Angeles 30.
For Orlando, Florida, and Houston, Texas, the entire summer could exceed the thresholds at which people have been known to die.
“People are talking about the future when it comes down to climate change, but what we found from this paper is that this is already happening. In fact since 1980 we found close to 2,000 cases of these places and cities when people died from this, and this is obviously going to get a lot worse,” Dr. Mora said.
The implication of the Hawaiian research is that if nations act in a concerted way to reduce fossil fuel emissions, an estimated 48 percent of the human population could be at risk of summer extremes. And if they do not, this hazard rises to 74 percent.
“Climate change has put humanity on a path that will become increasingly dangerous and difficult to reverse if greenhouse gas emissions are not taken much more seriously,” Dr. Mora said.
“Action like the withdrawal from the Paris Agreement is a step in the wrong direction that will inevitably delay fixing a problem for which there is simply no time to waste.”
On a spring day in May, temperatures in Dallas, Texas, were already in the 90s. Sunlight glinted off the barbed wire perimeter outside the Hutchins State Jail, located just a mile down down the road from Hutchins High School. The first blooms of Castilleja, colloquially known here as "prairie fire," seemed to set a field across from the prison ablaze.
It was hot outside, but it's nothing compared to the temperatures inside the Hutchins Unit, one of 79 state-run prison units still lacking air-conditioning in its cellblocks in 2017. Even those temperatures, though, still pale further in comparison with the extreme summer heat wave that broiled the jail on July 28, 2011, pushing the heat index up to about 150 degrees in the cellblocks, according to the state's own records, and transforming the jail into an oven that slowly baked Hutchins prisoner Larry McCollum alive.
McCollum, a 58-year-old cab driver from the Waco area, was found having convulsions in his top bunk. He was taken to Dallas' Parkland Hospital, where his body temperature was measured at 109.4 degrees. McCollum, who was incarcerated for writing a bad check, had recently begun serving his 11-month sentence, and was eager to get through his time and reunite with his wife and two children.
"He was taken from us. He was supposed to go in for 11 months, and he wound up with a death sentence," McCollum's daughter, Stephanie Kingrey, said. "It was very heartbreaking that he had to sit there and suffer as long as he did before they got any help for him or got him to emergency room."
During a summer heat wave in July of 2011, prisoner Larry McCollum died of heat stroke at the Hutchins State Jail in Dallas, Texas, pictured above. (Photo: Candice Bernd)
Kingrey said that officials with the Texas Department of Criminal Justice (TDCJ) even tried to deny her access to her father during the seven days he spent on life support at Parkland Hospital, eventually relenting as Kingrey and other relatives were forced to make the devastating decision to take McCollum off of life support.
"They had guards on him 24 hours, like he was just going to jump up and go somewhere, and he was handcuffed to the bed the whole time," Kingrey says. "He was literally brain dead, and there was nothing he could do. He didn't regain consciousness or anything. He wasn't there. He died back in the prison cell."
McCollum is one of 22 heat-related deaths that TDCJ has been forced to acknowledge in its prison units after litigation -- 10 of those deaths occurring during that same 2011 summer heat wave. But these deaths are likely the first few indications of what may be a much larger heat problem.
"[TDCJ] has acknowledged the deaths because we proved we knew about them," said Attorney Jeff Edwards, who is representing the McCollum family in an ongoing lawsuit against TDCJ, during an interview in his Austin office. "In fact, there are far more than [22] deaths because the only deaths that they count are confirmed autopsies with a diagnosis of hyperthermia. In order to get that diagnosis, you have to have a temperature north of 105 or 106 degrees. So unless you find the body and do an autopsy quickly, you're not going to have that diagnosis. [TDCJ] also doesn't count the probably 100 or more people who suffered heart attacks in the summertime where heat was a contributing factor, or people who suffered asthmatic deaths because heat contributed to that."
The medical risk of heat stroke increases significantly when the temperature rises to more than 90 degrees, and can lead to other causes of death like heart attacks. This is especially true for people with medical conditions such as diabetes, high blood pressure and other cardiovascular issues, as well as asthma and chronic obstructive pulmonary disease. The risk rises further still for people on medications that inhibit their ability to shed heat or sweat, or certain psychiatric medications. There aren't yet full statistics on how many prison deaths have involved heat as a significant contributing factor, but the number is likely to be much higher than deaths directly attributable to hyperthermia.
"One death is enough to cause concern -- two, three, you need to be reacting immediately," Edwards says. "What is so frustrating about this is ... you can solve the problem of death by heat stroke in the Texas prison system instantaneously. All you need to do is lower the temperature and you eliminate it.... [TDCJ is] making a choice to have people die in the same way a car company makes a choice not to fix a defective product and have some people die. It's the exact same cost-benefit analysis."
Internal TDCJ emails obtained by Truthout and Earth Island Journal reveal that a database within TDCJ's Health Services Division was developed to track not only heat-related deaths in TDCJ prison units, but also the number of instances of heat-related illness occurring across particular units. The datasets also track other factors contributing to the occurrence of heat-related illness, including how many of the prisoners experiencing these illnesses were on antipsychotic medications.
According to the records, staffers within the Health Services Division tracked a total of 46 heat-related illnesses in TDCJ units in 2010, 48 such illnesses between the months of June and July of 2011 alone, and another 59 illnesses between August 1 and August 16 of 2011. Health Services Division staffers tracked a total of 110 illnesses in 2011 through August 16 of that year, across scores of units. The records indicate that in 2011, a majority of prisoners were located in their cellblocks at the onset of the heat-related illness, and that several of the illnesses involved prisoners taking antipsychotic and other medications that make them more vulnerable to heat conditions.
While TDCJ Director of Public Information Jason Clark didn't respond to Truthout and Earth Island Journal's request for the total number of instances of heat-related illness within TDCJ units tracked by its Health Services Division, the records from 2010 and 2011 point to a pervasive heat problem within TDCJ cellblock areas. They also reveal that prison officials neglected to act: Despite tracking more than 100 instances of heat-related illness, they have yet to introduce climate controls in TDCJ cellblocks that currently lack them.
Edwards is litigating several other federal lawsuits over heat-related deaths inside Texas prisons. He is also working on cases that confront the desperate conditions for elderly and other medically vulnerable prisoners who are increasingly susceptible to extreme temperatures, including an ongoing class-action lawsuit in Houston challenging conditions in the Wallace Pack Unit near Navasota, a geriatric prison incarcerating predominantly elderly and disabled prisoners who require continuous medical care.
TDCJ officials are currently appealing US District Judge Keith Ellison's certification of class status to all current and future prisoners at the Pack Unit subjected to extreme temperatures in the Fifth Circuit Court of Appeals.
The Hutchins State Jail in Dallas, Texas, still lacks air-conditioning in 2017. (Photo: Candice Bernd)
"To give you an idea of the heat we are talking about: When was the last time you jumped in your car after it has set in the sun with windows rolled up on a 90° day? Now try to sit in it for 20 minutes!!!," writes 63-year-old prisoner John Ford, who is serving a 70-year sentence, from the Pack Unit. "The beds and cubicle wall are metal. They are hot and can't be laid on or touched, like touching the hood of a car that has sit in the sun on a 130-degree day. Most of us try to wet our sheets and the cement floor. We lay in the water, put the sheet over us while blowing the fan under the sheet, to keep the body temps down."
TDCJ's solution during periods of extreme heat was to tell Pack Unit prisoners to simply drink more water, recommending up to two gallons of water a day on extremely hot days. There was just one problem: The water at the Pack Unit contained between 2.5 to 4.5 times the level of arsenic, a carcinogen, permitted by the EPA, according to court documents. Many of the prisoners drank thousands of gallons of this arsenic-tainted water for more than 10 years before Judge Ellison ordered TDCJ to truck in clean water for the prisoners last year. TDCJ installed a modern filtration system in January.
"It used to be where you could take a white wash rag and put it in the sink and water would run on it about 10 or 15 minutes, and it would actually turn brown," says Keith Cole, 63, a lead plaintiff in the lawsuit who is serving a life sentence at the Pack Unit.
It's something the prisoners and their attorney say TDCJ knew about for years. "Inmates were breaking out with all kinds of skin issues, and skin cancers that still have been denied that it was caused by the water," Ford writes.
Both Ford and Cole, who arrived at the unit in 2015 and 2011, respectively, worry about how their prolonged exposure to arsenic may have affected their health over the long term, including their specific medical issues. Cole has been diagnosed with severe coronary artery disease, type II diabetes, hypertension and high cholesterol, and has had two stent implants. Ford has seven stent implants in his heart, high blood pressure, and "serious issues" with his bladder and kidney that he suspects are "from the chemicals."
They also worry about how their prolonged stress during exposure to periods of extreme heat for years may have impacted them long term. Ford says he suffers respiratory problems he believes are exacerbated not only by the extreme heat in the unit during the summer months, but also by the black mold he alleges to be present inside the prison.
A spokesperson with the University of Texas Medical Branch, which manages medical care at TDCJ units through its Correctional Managed Care division, declined to comment on the heat exposure, citing ongoing lawsuits.
"TDCJ takes precautions to help reduce heat-related illnesses such as providing water and ice to staff and offenders in work and housing areas, restricting offender activity during the hottest parts of the day, and training staff to identify those with heat related illnesses and refer them to medical staff for treatment," TDCJ Public Information Director Clark said. He also cited "access to respite areas" that are air-conditioned as a system-wide protocol that is utilized during periods of extreme heat.
Cole says that while he, personally, is being granted regular access to a respite area at the Pack Unit, he believes this is only because he is the primary plaintiff in a major ongoing class-action lawsuit. For other prisoners at the unit, he says, it is a protocol that exists only on paper.
"Even though [TDCJ] claims they have enough space to put every offender on this unit into respite at the same time, if offenders starting using respite on a large scale, let's say ... 20 percent of the inmates wanted to go to respite, that would pretty much shut down the day-to-day operations of this unit," Cole says. "So what they do is they find low-visibility ways to discourage offenders from using respite."
Cole says that prison officials regularly take Pack Unit prisoners to the infirmary, where nurses perform an internal core temperature check by inserting a thermometer into prisoners' rectums. "That's the first procedure they do before they do anything for you at all," he says. So many prisoners avoid asking for respite in the first place.
According to Clark, only 29 of 108 TDCJ units have air-conditioning in all "offender housing areas," with all units having at least some areas that are air-conditioned. Among the areas that TDCJ chooses to air-condition in its units are its prison armories and areas for livestock.
Guidelines from both the American Bar Association and the American Correctional Association (ACA) suggest that prison officials should provide adequate temperature control in cellblocks, but the ACA continues to accredit units lacking climate controls.
At this point, even unions representing prison guards, many of who have also experienced heat-related illnesses and injuries while on duty, have been supportive of lawsuits over extreme heat in TDCJ units.
Truthout and Earth Island Journal didn't receive any responsive records after requesting potential documents outlining TDCJ officials' plans to adapt their protocols and procedures in light of ongoing anthropogenic climate disruption and expectations for intensifying heat waves across the state in the coming decades. The lack of documents indicates that the state's prison officials may have no plans, outside TDCJ's current existing heat policies, for mitigating temperatures as more heat waves sweep Texas in years to come.
Indeed, periods of intense heat are expected to accelerate in the state, according to climate scientists like Linda Mearns.
Mearns is a senior climate scientist at the National Center for Atmospheric Research in Boulder, Colorado, and conducted a climate study on the region around Navasota, Texas, where the Wallace Pack Unit is located. Analyzing datasets from nearby weather stations in the area in order to predict future extremes, she not only found that both maximum and minimum average temperatures from all six weather stations analyzed are steadily increasing, but that the likelihood of extreme summer heat waves is expected to increase dramatically.
"We looked at the likelihood of the recurrence of extreme summer temperatures at the level of that summer of 2011 ... and essentially, going out into a period, let's say to 2035, we found that there's a eight-fold increase in the likelihood of that kind of extreme event repeating itself," Mearns says. "It's very clear that temperatures are increasing, that extremes of temperatures are increasing [in the region]."
Mearns also looked at trends in the number of days per summer that have exceeded certain temperature thresholds that can be dangerous to certain risk groups if left exposed. She looked at thresholds of 88, 95 and 100 degrees Fahrenheit and found that days exceeding those temperatures have been steadily increasing since 1970.
"In terms of the heat index, the major factor is still the temperature, so we see very distinct increases in the heat index, which is actually used to determine dangerous conditions for human health, and we see increases in those thresholds as well, for example, a heat index above 88 or above 95 for a particular length of time," Mearns says. According to her research, the median value of days with a heat index above 95 or 100 degrees lasting more than four hours per day increases to more than 20 days by 2035, and 55 days by 2055 in the area around Navasota.
It's the extremes that pose the greatest danger to vulnerable populations such as the elderly, or people with health conditions that render them at risk. According to Mearns, people for the most part become somewhat adapted to the climate that they live in, even as average temperatures increase. Extreme temperature changes, however, don't allow enough time for the body to properly acclimate -- one reason why nearly half of TDCJ's confirmed hyperthermia deaths all occurred during the same 2011 heat wave.
According to Edwards, experts testifying on behalf of TDCJ have acknowledged the reality of climate disruption, but, "Internally, they are loathe to answer [the climate] question because they are appointees of [the governor], and that question is fraught with danger in an oil state like Texas," he says. "They want to be looked at as tough on crime, and don't view air-conditioning or costs associated with air-conditioning as priorities until the courts tell them they have to."
Many of the state's prisons were constructed during the "tough-on-crime" prison boom of the 1990s, which hit particularly hard in Texas. "It wasn't as if [air-conditioning] was discussed," Michele Deitch, a senior lecturer at the University of Texas' Lyndon B. Johnson School of Public Affairs, says. "The prisons were just built."
According to Clark, many of TDCJ's units that were built in the 1980s and 1990s didn't include air-conditioning because of the added construction, maintenance and utility costs. This lack of air-conditioning persisted, despite the far-reaching 1980 court ruling Ruiz v. Estelle, which found that conditions of imprisonment within the TDCJ prison system constituted cruel and unusual punishment. Although the decision was the result of one of the most far-reaching lawsuits on incarceration conditions in US history, it didn't include conditions relating to extreme heat. Therefore, TDCJ units lacking air-conditioning in cellblocks continued to be approved by federal courts.
"One-hundred-thousand prison beds were constructed in a very crisis-oriented atmosphere where the goal was to build them very quickly and as cheaply as possible, to get these inmates out of the [county] jails [and into state prisons]," Deitch said. "When [the prisons] were constructed, the [state] legislature was never inclined to provide money, and the legislature help fund the construction of these facilities. They're expensive enough to build, and the legislature was not going to give any money to cover the cost of air-conditioning. That was just seen as treating prisoners too well."
The harsh sentencing practices of the '90s have left the state with a prison population that is now rapidly aging behind bars, and increasingly requiring extensive medical care. "In Texas with its super-long sentences ... the fastest-growing population is the geriatric population. With all of these inmates in un-air-conditioned facilities, I think we're going to be seeing a lot more deaths in custody from people who can't handle the heat," Deitch says.
In Texas, the price of politicians and prison officials' climate denial is human lives. Not only are the state's aging prisoners being rendered casualties of climate change, they are held captive to changing climate conditions, unable to adapt to the increasing heat waves, and, in the case of Wallace Pack, forced to endure other environmental degradations and injustices -- such as drinking arsenic-tainted water for more than 10 years -- to cope.
"Our tough-on-crime mentality about sentencing is bumping up against our-tough-on crime mentality in terms of extreme conditions for prisoners, and I think it's going to lead to some very tragic consequences, particularly as climate change makes the situation even worse," Deitch says.
Indeed, over his 23 years in the TDCJ system, Cole says the summers have become more extreme. "It seems to be getting more hotter now. I don't know if I can attribute that to the fact that temperatures are worse, or maybe the fact that I'm getting older and my diseases are progressing, but I know that the summers now are more intense to me than they were 10 years ago when I was in the system."
This report is part of a collaborative series on on the environment and mass incarceration by Truthout and Earth Island Journal. It was supported by a grant from the Fund for Investigative Journalism.
or a swath of states from New Mexico over to Florida and up to Ohio, 2017 has been the hottest year on record through April.
For the Lower 48 as a whole, the year is the second warmest in records going back to 1895.
Several states in the mid-Atlantic had their hottest April on record and a few Southeastern states were near-record warm, according to National Oceanic and Atmospheric Administration data released Monday.
State temperature ranks for January through April 2017. Red states were record warm for the year to date. Click image to enlarge. Credit: NOAA
The average temperature for the contiguous U.S. through April was 43.7°F (6.5°C), 4.5°F (2.5°C) above the 20th century average, NOAA said. This put the four-month period behind only 2012, which saw major heat waves and drought across much of the central part of the nation.
The exceptional heat of February is what’s keeping 2017 so high in the rankings, Jake Crouch, a NOAA climatologist, said in an email. With eight months left, though, it is unclear whether 2017 will stay warm enough to ultimately beat 2012 as the hottest calendar year for the Lower 48.
“I think that the potential development of the El Niño and how the drought conditions expand or intensify going into summer will be the two things to watch on determining how warm 2017 ultimately ends up being,” Crouch said. The current forecast slightly favors the development of El Niño in late summer or fall.
During April, the eastern half of the country was the center of warmth, with the West Coast running closer to average. North Carolina, Virginia, West Virginia, Maryland, New Jersey, Pennsylvania and Ohio all had their hottest April. Several other states surrounding that area had a top 5 warmest April.Fourteen states along the southern tier of the country and up the Ohio Valley are record hot for the year so far, with another 17 states having a top 5 warmest year through April. Numerous cities in those states, including Atlanta, Washington, D.C., Miami and Charleston, S.C., are also running record hot so far in 2017, according to the Southeast Regional Climate Center. Only the Pacific Northwest had temperatures at or below average for the year.
Two natural climate patterns, called the North Atlantic Oscillation and the Arctic Oscillation, were in phases that tend to bring warm conditions to the eastern U.S., Crouch said. The phases of those patterns have just switched, bringing the much cooler conditions of the last couple weeks.
State temperature ranks for April 2017. Red states were record warm for the year to date. Click image to enlarge. Credit: NOAA
But rising global temperatures have also titled the balance in favor of more record heat. April was the 29th month in a row where heat records outpaced cold records in the U.S., the longest such stretch in the books and 10 months longer than the previous record stretch. Of the five longest such streaks, four have occurred since 1998 (in a stable climate, record heat and record cold would be roughly even over time).
Global temperatures are rising because of the continued release of heat-trapping greenhouse gases into the atmosphere. The most important of those gases, carbon dioxide, recently passed the threshold of 410 parts per million at the Mauna Loa observatory in Hawaii for the first time in recorded history.
Global temperatures for April will be released next week by both NOAA and NASA, but through March, 2017 was the second hottest year on record. It trailed behind only the record heat of 2016, which was the third record-hot year in a row.
Deadly heat stress is projected to affect hundreds of millions more people each year under relatively little additional climate warming. The Paris Agreement commits the international community to limit global warming to no more than 2℃ above pre-industrial (late 19th century) air temperatures, with an aspirational target of 1.5℃. In our latest research, which looked at the impact of global temperature rises on megacities, we found that even if 1.5℃ is achieved, large increases in the frequency of deadly heat are expected.
By 2050 about 350m more people living in megacities could be exposed to deadly heat each year.
Humans become “heat stressed” when the body absorbs more heat than is tolerable. If core body temperature rises just a few degrees above 37℃, deadly heatstroke can result. By using its cooling system – sweating – the human body can maintain a safe temperature even if air temperatures rise above 37℃. This mechanism works better in a drier atmosphere (which is why steam rooms feel hotter than saunas – even at the same air temperature). The heat index is a measure that combines this humidity effect with air temperature to provide a “feels like” temperature. A heat index in excess of about 40.6℃ is considered dangerous to human health.
As global air temperatures rise, observations and experiments with climate models suggest that atmospheric moisture content also climbs. This means that the heat index (and how hot it feels) rises faster than air temperature. Also, because the amount of moisture the atmosphere can hold increases more rapidly at higher temperatures, the heat index rises faster too (a non-linear response).
Strong incentive to limit global warming
This non-linear response carries over to the definition of “global heat stress burden” used in our research, which we define as the average number of days per year over land areas with a daily heat index above 40.6℃. Using a large number of climate model simulations, we found that this quantity increases faster and faster as global average air temperatures rise. This sharp rise in global heat stress burden has important consequences.
First, any increase in global heat stress from climate warming to date will be smaller than that caused by the same additional warming in the future. (We have seen a 0.8℃ rise in global temperature; another 0.8℃ of warming could be expected to lead to a greater increase in heat stress than caused by the first 0.8℃.)
Second, there may be progressively heavier global impacts if the Paris targets are breached. Our analysis suggests that for 1.5℃ warming, the global heat stress burden will be almost six times greater than experienced during 1979-2005. But heat stress is 12 times greater if warming reaches 2℃. With 4℃ warming – which could happen if mitigation efforts fail – our analysis suggests that the global heat stress burden could be more than 75 times larger.
Such large increases in heat stress may be hard to imagine, so we used recent heat waves to help communicate the impacts that may lie ahead.
For example, in 2015, Karachi and Kolkata in India experienced lethal temperatures. Our analysis suggests that in a 2℃-warmer world, both cities could experience these deadly conditions at least once a year. If global warming reaches 4℃, the record heat of 2015 would be commonplace – more than 40 days a year. Other regions would not be immune. With only 1.5℃ of warming, twice as many global megacities (cities with a population greater than 10m, including Lagos, Nigeria, and Shanghai, China) could start to regularly experience heat stress. At 2℃, Tokyo (the world’s most populous city), may be affected. New York City joins the list at 4℃.
If the global population grows as anticipated this century, it could drive up global heat stress even more. The situation in Lagos illustrates this well. If global warming reaches 1.5℃ by the end of the century (at which time the population of Lagos may have increased elevenfold and dangerous heat may be 100 times more common) the heat stress burden could be more than a thousand times greater than the recent past.
Across all megacity regions, if the 1.5℃ limit is breached by the 2050s, as many as 350m people globally could be regularly exposed to dangerous heat stress. This is more than a fourfold increase compared with 1979-2005.
Heat stress sensitivity to global temperature rise and the potential human impacts – even at 1.5℃ above pre-industrial levels – provide a strong incentive for limiting global warming. Warming associated with the Paris targets may sound modest enough for the urgency of the situation to be lost. Our analysis shows that even if ambitious mitigation targets are met, the need to adapt to extreme heat will remain. The high concentration of people and heat in urban environments make cities an important focus for these adaptation efforts.
The WMO’s assessment of the climate in 2016, published on Tuesday, reports unprecedented heat across the globe, exceptionally low ice at both poles and surging sea-level rise.
Global warming is largely being driven by emissions from human activities, but a strong El Niño—a natural climate cycle—added to the heat in 2016. The El Niño is now waning, but the extremes continue to be seen, with temperature records tumbling in the US in February and polar heatwaves pushing ice cover to new lows.
“Even without a strong El Niño in 2017, we are seeing other remarkable changes across the planet that are challenging the limits of our understanding of the climate system. We are now in truly uncharted territory,” said David Carlson, director of the WMO’s world climate research programme.
“Earth is a planet in upheaval due to human-caused changes in the atmosphere,” said Jeffrey Kargel, a glaciologist at the University of Arizona in the US. “In general, drastically changing conditions do not help civilisation, which thrives on stability.”
The WMO report was “startling”, said Prof David Reay, an emissions expert at the University of Edinburgh: “The need for concerted action on climate change has never been so stark nor the stakes so high.”
The new WMO assessment also prompted some scientists to criticise Donald Trump. “While the data show an ever increasing impact of human activities on the climate system, the Trump administration and senior Republicans in Congress continue to bury their heads in the sand,” said Prof Sir Robert Watson, a distinguished climate scientist at the UK’s University of East Anglia and a former head of the UN’s climate science panel.
“Our children and grandchildren will look back on the climate deniers and ask how they could have sacrificed the planet for the sake of cheap fossil fuel energy, when the cost of inaction exceeds the cost of a transition to a low-carbon economy,” Watson said.
Trump is aiming to cut climate change research. But the WMO’s secretary-general Petteri Taalas said: “Continued investment in climate research and observations is vital if our scientific knowledge is to keep pace with the rapid rate of climate change.”
2016 saw the hottest global average among thermometer measurements stretching back to 1880. But scientific research indicates the world was last this warm about 115,000 years ago and that the planet has not experienced such high levels of carbon dioxide in the atmosphere for 4m years.
“Arctic ice conditions have been tracking at record low conditions since October, persisting for six consecutive months, something not seen before in the [four-decade] satellite data record,” said Prof Julienne Stroeve, at University College London in the UK. “Over in the southern hemisphere, the sea ice also broke new record lows in the seasonal maximum and minimum extents, leading to the least amount of global sea ice ever recorded.”
Emily Shuckburgh, at the British Antarctic Survey, said: “The Arctic may be remote, but changes that occur there directly affect us. The melting of the Greenland ice sheet is already contributing significantly to sea level rise, and new research is highlighting that the melting of Arctic sea ice can alter weather conditions across Europe, Asia and North America.”
Global sea level rise surged between November 2014 and February 2016, with the El Niño event helping the oceans rise by by 15mm. That jump would have take five years under the steady rise seen in recent decades, as ice caps melt and oceans get warmer and expand in volume. Final data for 2016 sea level rise have yet to be published.
Climate change harms people most directly by increasing the risk of extreme weather events and the WMO report states that these raised risks can increasingly be calculated. For example, the Arctic heatwaves are made tens of times more likely and the soaring temperatures seen in Australia in February were made twice as likely .
“With levels of carbon dioxide in the atmosphere consistently breaking new records, the influence of human activities on the climate system has become more and more evident,” said Taalas.
NASA and NOAA jointly reported that 2016 was the warmest year on record. That’s no surprise, as the first six months of the year were all exceptionally warm.
Yet the news is significant for what it says about global warming: Before 2016, the 10 hottest years on record occurred since 1998. And last year was the third consecutive year a new global annual temperature record has been set.
Despite the ongoing record-breaking heat planet-wide, skepticism over anthropogenic, or human-made, global warming remains. To some, the fact that meteorologists can’t reliably forecast the weather days in advance is proof that scientists can’t predict the Earth’s climate years or decades from now.
Why do scientists like myself have confidence in predicting record heat months in advance, and how do climate predictions differ from weather forecasting?
Weather forecasts based on motions of the atmosphere
Weather forecasts take into account the evolution of weather systems, including atmospheric pressure patterns. Atmospheric pressure is the force exerted by the weight of air molecules. Areas where air is sinking have high pressure, and generally warm and fair weather. Low pressure systems, also known as cyclones, occur where air rises and typically produce cooler and wet weather.
This map shows ranking for 2016 annual average temperature by state. Rankings refer to the 122-year period of record 1895-2016. A rank of 122 indicates record warmth. 2016 was the second-warmest year on record for the contiguous US. (image: NOAA)
The accuracy of weather forecasts up to around two weeks out has improved greatly in recent years. But atmospheric systems don’t persist long, and predictions beyond that time frame become much less accurate.
For example, forecasting the formation of low-pressure systems (cyclogeneis) and movement across the east coast of the U.S. presents a challenge. A deviation from the forecast track of just 50 miles east or west can mean the difference between a blizzard, a windswept rainstorm or a near miss.
Similarly, forecasts of the amount of rain that will fall on a hot summer day can be very uncertain. When a forecast calls for “isolated thunderstorms,” factors controlling storm formation, such as daytime heating, moisture flow and upper-level winds, are expected. But those factors evolve considerably during a given day, making it difficult to forecast total rainfall, particularly over a small area. So it’s hard to say if it will rain on your parade or the next town over – the term “pop-up” thunderstorm is apt.
That’s not to say that warnings for severe storms should not be trusted. In this case, forecasts of severe weather are often made for larger geographical regions, and only when the conditions exist. The factors that produce severe weather span a larger area compared with those leading to isolated storms. Technological improvements, including better radar and the use of supercomputers, are also leading to more accurate severe weather forecasts.
Role of ocean heat
In contrast to forecasts based on the movement of transient weather systems, climate predictions around temperature and precipitation, for example, use completely different sets of data.
To forecast several months to several decades into the future, scientists make use of ocean variations, other natural factors (solar variations, volcanic eruptions), and the overarching influence from rising greenhouse gas (GHG) concentrations in the atmosphere. These variables evolve and exert their influence over months and years, unlike atmospheric pressure patterns which can change within hours or days.
One important factor with an effect of several months to about a year is El Niño, the periodic warming of ocean temperatures across the tropical Pacific. This pattern of ocean warming and associated effects on the atmosphere exerts a strong influence beyond the tropics that can factor into climate predictions.
This map shows the blended land and sea surface temperature anomalies, or changes from historical averages, for 2016 in degrees Celsius. (credit: NOAA National Centers for Environmental Information)Data on ocean temperatures are critical because most of the sun’s radiation striking Earth is absorbed by the world’s oceans. Driven by this energy, oceans and the atmosphere distribute heat around the globe.
Years following an El Niño tend to be warmer than those with near-normal (also called neutral) or La Niña conditions. The presence of La Niña often results in a lowering of global temperature. This tells us that the relative amount of heat in surface waters of the tropical Pacific can be used to predict global temperatures several months in advance, which is exactly what happened in forecasting last year’s record temperature.
In December 2015 the U.K. Met Office predicted that 2016 would be record warm, between 0.72 and 0.96 degrees Celsius above the long-term (1961-1990) average. Their announcement today that 2016 was 0.77℃ above average is within the predicted range. In early 2016 Gavin Schmidt from NASA’s Goddard Institute for Space Studies predicted that 2016 would be 1.3℃ above late 19th-century temperatures – remarkably close to today’s reported 1.2℃ rise.
What about 2017? In its Jan. 12 update, NOAA forecasted a transition from weak La Nina to neutral conditions through the first half of 2017. La Niña’s influence early in the year is central in predictions that 2017 will be slightly cooler than 2016, but still among one of the hottest years on record.
Global annual average near-surface temperature anomalies (i.e., temperature difference from the 1961-1990 average in degrees Celsius) from 1850-2015. The 2016 value is an average for January to October. The gray line and shading shows the 95 percent uncertainty range. The forecast value for 2017 and its uncertainty range are shown in green and black. (credit: UK Met Office)
It should be added that the record 2016 warmth was not due to El Niño alone. Indeed, El Niño years are becoming warmer, as are those with a La Niña, due to the overall warming trend from rising GHG concentrations.
Combined influence of human and natural factors over time
Cooling, however, is typically short-lived and ends when the volcanic aerosols – the small particles that block sunlight – rain out.
Variations in solar output can also influence climate. The observed warming trend over recent decades, however, cannot be attributed to changes in the sun. The impact of solar variability on climate change is evident, but the effect of GHGs has been proven much more considerable in the short run.
Projections of warming at longer time scales – multiple decades or longer – are based on simulations by climate models and our understanding of how sensitive the climate system is to future increases in atmospheric GHG concentrations.
What models have shown is that future warming is expected to be dominated by the rising GHG levels as compared with the variations from internal ocean variability and other natural factors. The warming will be amplified by feedbacks involving the carbon cycle, atmospheric moisture and other factors. For example, water vapor is a potent GHG, so rising atmospheric moisture amounts will enhance warming. Also, emissions from the Arctic are a particular concern and threaten to switch the Arctic from a sink of carbon to a source.
Sixteen of the 17 hottest years have occurred this century. There is an overwhelming scientific consensus that human actions are warming the planet.
At the same time, we continue to improve weather and climate predictions, which will lead us to a deeper understanding of climate system behavior over different time periods and across multiple spatial scales. This research will improve the accuracy – and confidence – in projections for the future.
In less than two weeks, 2016 will officially be the hottest year on the books in more than 120 years of record keeping by U.S. agencies.
It will be the third straight record-setting year — and of the 17 hottest years, 16 have been this century — a clear sign of the human-caused rise in global temperatures caused by the buildup of heat-trapping greenhouse gases over the past century. The world is already more than halfway down the road to surpassing the Paris climate pact goal to limit warming to less than 2°C (3.6°F) by 2100.
The running average of global temperatures throughout 2016 compared to recent years. Each month shows the average of that month's temperature and each month before it.
These milestones have climate scientists and policymakers concerned about keeping that goal, particularly as the incoming Trump administration will almost certainly be filled with cabinet members who reject the established science of climate change.
November was the second warmest on record (after November 2015), according to NASA data released last week, with an average temperature 1.71°F (0.95°C) above the 1951-1980 average.
The National Oceanic and Atmospheric Administration ranked the month slightly lower, in the fifth warmest spot, according to a report released Monday. It put the global temperature for the month at 1.31°F (0.72°C) above the 20th century average.
For the year-to-date, 2016 is 1.69°F (0.94°C) above the 20th century average, according to NOAA, and 1.84°F (1.02°C) above the 1951-1980 average according to NASA.
Each agency uses different baselines of comparison and processes global temperature data in slightly different ways, leading to small differences in the final numbers for particular months and years. Both, though, have shown clear agreement in overall warming trends, and expect 2016 to easily set the record in their respective datasets.
While a very strong El Niño helped boost temperatures during this year and last, the record-setting temperature is mostly due to the long-term warming driven by human activities. Even years marked by El Niño’s cold counterpart, La Niña, are now warmer than El Niño years of previous decades because of this warming.
Last year, the world agreed to limit warming to no more than 2°C above pre-industrial levels by the end of this century and to try to keep it under 1.5°C. To show how close global temperatures already are to the second goal, Climate Central has been reanalyzing the monthly temperature data to compare it to a baseline closer to pre-industrial.
Averaging NASA and NOAA’s data, 2016’s temperature through November is 1.23°C (2.21°F) above the average from 1881-1910.
One major area of warmth during both November and the year as a whole was the Arctic. During November, the Arctic saw an almost unprecedented sea ice retreat, capping off a year that has shocked even seasoned Arctic researchers. The winter sea ice peak was the lowest on record (beating out 2015) and the summer minimum was the second lowest. Air temperatures in the region have continually been above average by double digits.
How temperatures around the world compared to normal for the year so far.
One reason NOAA’s global temperature for November may have been lower than NASA’s is that it doesn’t incorporate Arctic temperatures.
Another hotspot for November was North America; the contiguous U.S. is poised to have its second-hottest year on record.
Many climate scientists have expressed concern over some of President-elect Trump’s nominees to key cabinet posts, such as the departments of Energy and State. Rick Perry, the Energy nominee, has dismissed the reality of climate change, and Rex Tillerson, nominee for secretary of state, is CEO of ExxonMobil, which spent decades ignoring its own scientists’ research tying fossil fuels to climate change.
There is concern that with these players, the incoming administration will roll back progress toward combating climate change, causing the world to charge past its goals of limiting warming.
It’s fall, and all across America, kids are heading back to school. Gone are the carefree days of summer. Returned are the exams that shape students’ futures—from next year’s course load to college graduation.
While study sessions and tutors are go-to tactics to boost grades, new research is uncovering the impact climate change may have on scholastic performance. Studies show that heat and carbon pollution impair cognition, hamper learning and undermine student achievement. For students and parents, our changing climate is becoming another hurdle on the path to academic success.
Heat drives down test scores
“My kids are in terrible moods when it’s hot out. They lose their appetite and need to drink significantly more water to stay hydrated,” said Leigh Garofalow, a New Jersey mother of two. “We live where I grew up, and summers were never like this for me.”
“My daughter had heat exhaustion two separate times during this summer’s heatwaves,” said Garofalow, who is a member of the Climate Reality Leadership Corps. “She got a headache, nausea and vomited on both occasions. We had to put her in a cool bath and feed her ice to make her feel better.”
Heatwaves aren’t just fueling headaches and dehydration. They are also driving down test scores. A 2015 study from the National Bureau of Economic Research looked at the effect of heat on student achievement. The authors examined standardized test scores of 8,000 students over nearly two decades across the United States. Then, they determined the average temperature in each child’s county on the day of her test to see how outside temperature impacted performance.
Math scores started to drop off when the temperature outside topped 22º C (71.6º F). While heat had no apparent effect on reading comprehension, the authors noted that “mathematical problem solving utilizes functions of the brain that are distinct from the other subject areas, and different parts of the brain are differentially affected by temperature.”
Students performance measured in percentile change alongside outdoor temperature on the day of the test. Source: Zivin, Hsiang, & Neidell, 2015.
Theses findings line up with priorstudies showing that heat impairs memory, limits attention and slows information processing. In short, more heat means more mental errors.
“There’s a saying that says ‘teachers can make the weather in their classroom’ — but it really is harder when the actual weather is creeping into the room!” said Rebecca Egler, a New York City schoolteacher.
“Hot days are definitely some of the hardest to teach on. When the building is really hot, students are generally (and understandably) more lethargic and often distracted,” said Egler. “Much of this is often due to low, or non-functioning air conditioners, which are often an issue only in schools that serve low-income students.”
Carbon pollution impairs cognitive function
The pollution driving the rise in temperatures also has a direct impact on human health, and kids are particularly vulnerable.
“My son has asthma, so hot, polluted days make it hard for him to breathe and run around and play — which are the hallmarks of childhood,” said Garofalow. “I hate to see him out of breath, wanting to come inside.”
Scientists have long understood traditional pollutants are bad for brains. Now, they are beginning to understand that atmospheric carbon dioxide — thought by many to be harmless in small doses — can also impair cognition.
A recent study from the Harvard School of Public Health found that cognitive performance dramatically worsened as indoor concentrations of carbon dioxide rose to 1,000 and 1,500 parts per million. (For a fuller accounting of these effects, see ThinkProgress’sreporting on carbon dioxide and cognition.)
As carbon dioxide concentrations rose, cognitive performance declined across several measures. Source: Allen et al., 2016
This poses a challenge because carbon dioxide concentrations tend to be higher in cities and much higher indoors, particularly where bodies are crowded and ventilation is poor. A 2012 study on indoor carbon pollution noted that CO2 concentrations in primary school classrooms in California and Texas regularly exceeded 1,000 parts per million ppm and could reach as high as 3,000 ppm. The average atmospheric level of carbon dioxide currently stands at around 400 ppm.
This is a problem we have seen before.
Fossil fuels are often likened to tobacco — dangerous, addictive and sold by powerful moneyed interests. But, in this case, lead may offer a better point of comparison.
For most of the 20th century, gas companies added tetraethyl lead to gasoline to boost octane levels and improve fuel efficiency. Scientists knew long ago that lead posed a threat to human health, but it wasn’t until 1973 that the Environmental Protection Agency began to phase out lead from gasoline. For decades, automakers and oil companies denied findings that lead distorted brains, producing learning disorders and violent or impulsive behavior.
As lead was removed from gasoline and other products, violent crime and teen pregnancy dropped. IQ scores rose. An entire generation was smarter, safer and healthier as a result.
Carbon pollution and severe heat may one day be seen as like the lead of the 21st Century — a pervasive environmental hazard that undermines the cognitive function of children everywhere, making school more challenging and less fruitful. For policymakers, the challenge is similar. How do you phase out a dangerous product that people use every day?
There are ways to cope with heat and indoor carbon pollution, including better ventilation and air conditioning. Garofalow said that air conditioning has made it easier for her daughter to concentrate because, “when she is hot she can only think about being hot, not what the teacher is saying.” As with most carbon quandaries, the best remedy is to cut emissions of the heat-trapping gas.
“My students are bright, hardworking and passionate, and I hate the idea that irreparable environmental damage is going to prevent them from contributing fully to our society,” said Egler. “They have a lot to give us, and we will collectively miss out if they are unable to do so."
Our findings demonstrate that there is an urgent need for climate change planning efforts that give all urban residents a voice. They also show the importance of conducting research with communities that will be most affected by climate change’s adverse impacts on city dwellers.
