States look to help tenants pay for air conditioning as climate warms

Read the full story at Stateline.

Some states where air conditioning used to be a luxury that was needed only a few days a year are now looking at ways to help people stay cool in the increasingly hot summers.

Study finds that Mississippi River Basin could be in an ‘extreme heat belt’ in 30 years

Read the full story from Investigate Midwest.

A climate study released during one of the hottest summers on record predicts a 125-degree “extreme heat belt” will stretch across a quarter of the country by 2053.

Extreme heat + air pollution can be deadly, with the health risk together worse than either alone

Bad air pollution and extreme heat each raise health risks, but they’re worse combined. Brian van der Brug/Los Angeles Times via Getty Images

by Erika Garcia, University of Southern California; Md Mostafijur Rahman, University of Southern California, and Rob Scot McConnell, University of Southern California

On the morning news, you see the weather forecast is for high heat, and there is an “excessive heat watch” for later in the week. You were hoping the weather would cool down, but yet another heat wave is threatening human health and increasing the chance of wildfires. On top of these warm days and nights, air quality data has been showing unhealthy levels of pollution.

Sound familiar? This scenario is increasingly the new normal in many parts of the world.

High heat and air pollution are each problematic for human health, particularly for vulnerable populations such as older adults. But what happens when they hit at the same time?

We examined over 1.5 million deaths from 2014 to 2020 registered in California – a state prone to summer heat waves and air pollution from wildfires – to find out.

Deaths spike when both risks are high

The number of deaths rose both on hot days and on days with high levels of fine particulate air pollution, known as PM2.5. But on days when an area was hit with a double whammy of both high heat and high air pollution, the effects were much higher than for each condition alone.

The risk of death on those extra-hot and polluted days was about three times greater than the effect of either high heat or high air pollution alone.

The more extreme the temperatures and pollution, the higher the risk. During the top 10% of hottest and most polluted days, the risk of death increased by 4% compared to days without extremes. During the top 1%, it increased by 21%; and among older adults over age 75, the risk of death increased by more than a third on those days.

Why risks are higher when both hit at once

There are several ways the combined exposure to extreme heat and particulate air pollution can harm human health.

Oxidative stress is the most common biological pathway linked with particulate air pollution and heat exposure. Oxidative stress is an imbalance between production of highly reactive molecules known as reactive oxygen species, or ROS, and the body’s ability to remove them. It’s been linked with lung diseases, among other illnesses.

Antioxidants help clean up these molecules, but particulate air pollution and heat disrupt this balance through excessive metabolic ROS production and lowered antioxidant activity.

Our research also showed that the effects of particulate air pollution and heat extremes were larger when high nighttime temperature and pollution occurred together. High nighttime temperatures can interfere with normal sleep and potentially contribute to chronic health conditions such as heart disease and obesity, and disrupt how the body regulates temperature.

Older adults may be more susceptible to effects of extreme heat and air pollution exposure, in part because this stress comes on top of age-related chronic health conditions like heart disease, high blood pressure, diabetes or chronic lung disease. Impaired body temperature regulation in response to heat can also occur with aging. And older adults may be less mobile and therefore less able to get to cooling centers or to medical care and be less able to afford air conditioning.

A future of high temperatures and air pollution

This isn’t just a California problem. Climate change will increase exposure to high heat and air pollution in many parts of the country.

Yearly average temperatures in the U.S. are already more than 1.8 degrees Fahrenheit (1 degree Celsius) warmer than at the beginning of the 1900s. By the end of this century, global temperatures are on pace to be nearly 5 F (2.7 C) warmer. Dangerous extreme heat waves, currently rare, will become more common.

Changing climate is also affecting levels of outdoor fine particulate pollution – for example, through weather changes such as air stagnation events, wind and dust storms, and drier and warmer conditions that contribute to increasingly frequent and intense wildfires.

What to do to stay safe

Further research is needed to better understand these effects, such as the full impact of wildfire smoke exposure. However, enough is known that people should take measures to reduce their risk of harm during periods of extreme heat or air pollution.

That means staying well hydrated and keeping cool. Shopping malls and other air-conditioned public spaces can provide a refuge from heat. Home air conditioning, especially during nighttime, can reduce mortality. A portable air filter in the bedroom can markedly reduce particle pollution levels.

People with symptoms of heat stress, such as headache, nausea, dizziness or confusion, especially the elderly, should seek medical care.

Many county and state health departments already provide alerts about extreme heat and extreme air pollution. Developing a special category of alert during co-occurring extremes may be beneficial to public health.

Governments also need to take steps now to avoid the worst future climate change scenarios. Some best practices for cities include creating cooling shade cover and green space that will also reduce particle pollution.

This article was updated Aug. 31, 2022, with heat advisories in the West.

Erika Garcia, Assistant Professor of Population and Public Health Sciences, University of Southern California; Md Mostafijur Rahman, Postdoctoral Scholar and Research Associate in Environmental Health, University of Southern California, and Rob Scot McConnell, Professor of Population and Public Health Sciences, University of Southern California

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Towns may grow millions more trees with $1.5B for urban forestry

Read the full story at Stateline.

States and cities across the country are beginning to embrace trees as critical infrastructure in urban areas. Neighborhoods with tree cover are significantly cooler than exposed areas known as “heat islands,” which can affect human health and utility bills. Urban forests absorb stormwater runoff, filter pollution from the air and sequester carbon.

As climate change threatens to bring increased heat waves, flooding and severe weather to many communities, some leaders are looking to trees as a potential solution. Some regions have been scrambling to restore urban forests that have been decimated by pests such as the emerald ash borer. And much like foresters in the Evergreen State, they may suddenly have more funding to help those efforts take root.

The Inflation Reduction Act, signed into law this month by President Joe Biden, includes $1.5 billion for the U.S. Forest Service’s Urban and Community Forestry Program, which supports efforts ranging from big cities to small communities. Agency leaders say the funding, which will be allotted through competitive grants, will be focused on reaching neighborhoods that lack green infrastructure and are bearing the brunt of climate change.

These maps show how many ‘dangerous’ heat days your neighborhood may have by midcentury

Read the full story at Fast Company.

See also Rise in extreme heat will hit minority communities hardest at E&E News, which includes additional analysis that combines First Street’s data with Census Bureau records to analyze racial and ethnic disparities in exposure to extreme heat.

Right now, there are only a few pockets of the U.S. where it’s possible that the heat index might rise above 125 degrees Fahrenheit—a particularly dangerous threshold for human health. But by the middle of the century, a much larger area is at risk, sprawling from the Gulf Coast across a swath of the middle of the country, and reaching as far north as southern Wisconsin.

A new report [by First Street] maps out where it could happen, along with the increased risk of more ordinary (but still risky) extreme heat, heat waves, and temperatures that surge outside local norms. In a new tool, you can type in any American address, and see both the risks from heat in your neighborhood now and by midcentury. It’s part of Risk Factor, a broader climate risk tool that also shows the risk from flooding or wildfires for any American address.

A climate scientist on the planet’s simultaneous disasters, from Pakistan’s horror floods to Europe’s record drought

by Andrew King, The University of Melbourne

Extreme floods are devastating Pakistan, caused by a combination of heavy monsoon rains and melting glaciers. While Pakistan is no stranger to deadly floods, this event is especially shocking with more than 1,100 people dead so far and many millions more affected.

Pakistan’s climate chief has said one-third of the country is underwater – an area larger than the state of Victoria.

This Northern Hemisphere summer has seen extreme weather event after extreme weather event, from record-breaking drought in Western Europe, the United States and China, to flooding in Japan and South Korea.

This begs the question of the extent climate change is to blame. And, if so, is this what we should expect from now on?

A summer of extremes

The flooding in Pakistan is the latest in a sequence of exceptional disasters in the Northern Hemisphere.

Western Europe and central and eastern China have experienced record-breaking heatwaves and droughts leading to water restrictions. These heatwaves and droughts have also caused crop shortages, which are adding to the rising costs of food around the world.

China was plunged into an energy security crisis. And Italy’s longest river is flowing at one tenth of its usual rate. These droughts and their significant impacts are forecast to continue for the foreseeable future.

Severe downpours have caused floods in places ranging from Dallas in the United States to Seoul in South Korea, which experienced its heaviest torrential rain in a century.

Record-breaking heat extremes have also been recorded in Japan, the central US and in the UK, where temperatures exceeded 40℃ for the first time.

It has also only been a few months since we saw temperatures reach 50℃ ahead of the monsoon rains in northern India and Pakistan.

Temperatures in the UK recently edged over 40℃ for the first time on record. EPA/ANDY RAIN

Putting it into perspective

While it’s true that several of this summer’s extreme events have been exceptional, we normally see more high-impact extreme weather events in Northern Hemisphere summer than any other time. This is because extreme heat, very heavy downpours, and drought are more likely at the warmest time of year.

Two-thirds of the planet’s land and more than 85% of the world’s population are in the Northern Hemisphere. This means there are more people to be affected by extreme weather than in the Southern Hemisphere, making the Northern Hemisphere summer the prime time for disasters to have severe impacts.

Additionally, extreme weather events can occur at the same time over different places, because of large-scale atmospheric waves called “Rossby waves”, which are a naturally occurring phenomenon, like La Niña and El Niño.

Soldiers carry debris after the floodwater drained from submerged houses following heavy rains in Seoul, South Korea. Kiim In-chul/Newsis via AP

Back in 2010, western Russia experienced severe heat and wildfires while Pakistan had some of their worst floods to date. These events were connected by a Rossby wave causing a high pressure pattern to get stuck over western Russia and low pressure to persist over Pakistan.

Rossby waves can also result in heatwaves occurring at the same time, thousands of kilometres apart. Earlier this Northern Hemisphere summer, we saw simultaneous heatwaves strike the western US, western Europe and China.

Rossby waves may well have contributed to simultaneous disasters this summer, but it’s too soon to say for sure.

Climate change and the never-ending extremes

With so many extreme weather events causing mass deaths and large economic and environmental problems, it’s worth considering whether climate change may be making these events worse.

Human-caused climate change has warmed the planet by about 1.2℃ to date and this has caused some types of extreme weather to become more frequent and more intense, particularly extreme heatwaves and record-high temperatures.

Corn fields are completely dry in the Kochersberg, in eastern France. AP Photo/Jean-Francois Badias

Every heatwave in today’s climate has the fingerprint of climate change resulting from our greenhouse gas emissions. Indeed, rapid analyses have already demonstrated that the human effect on the climate greatly increased the likelihood of the extreme heat in India and Pakistan in May, and the record high UK temperatures in July.

Research also shows climate change is increasing the occurrence of simultaneous heatwaves in the Northern Hemisphere, mainly due to long-term warming.

It’s less clear whether the Rossby wave pattern that causes simultaneous heatwaves in different places is becoming more frequent.

Climate change is also shifting rainfall patterns resulting in worsening drought in some areas, such as in much of Western Europe.

And severe downpours and extreme short-duration heavy rain, such as that seen in Seoul and Dallas in recent weeks, are being intensified by climate change. This is because global warming results in the air being able to hold more moisture – for every 1℃ of warming, the atmosphere can hold 7% more moisture.

Indeed, the heavy rains in Pakistan follow an observed trend towards increasing extreme daily rainfall totals. This area of the world is projected to see a continued intensification of daily and multi-day extreme rain events over summer, as the planet warms.

Maximum 5-day rainfall in June-August is projected to increase in Pakistan at 2°C global warming. IPCC AR6 Interactive Atlas

Worse extremes to come

We can expect more extreme weather events in the coming years as global greenhouse gas emissions continue at near-record rates.

Scientists have been predicting worsening extreme weather events – particularly heatwaves – for decades. Now, we are seeing this happen before our eyes.

Some heat extremes in recent years have been far beyond what we thought would happen after just over 1℃ of global warming, such as western North America’s record heat of last summer. But it’s hard to tell if our projections are under-forecasting extreme heat.

In any case, the world must prepare for further possible record-shattering high temperatures in the months, years and decades to come. We need to rapidly decarbonise to limit the damage caused by future extreme events.

Andrew King, Senior Lecturer in Climate Science, The University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.

As extreme heat grips the globe, access to air conditioning is an urgent public health issue

Read the full story from the Brookings Institution.

Through indoor air conditioning, the U.S. is much better equipped to keep people safe during periods of extreme heat compared with a century ago. Nationally, about 70% of homes now have central AC, while about 10% of households have no air conditioning. But the presence and type of home AC varies considerably by geography. Like exposure to other climate risks, protection from extreme heat also varies by income, tenure, and race. 

A day with America’s only dedicated heat team in the US’s hottest city

Read the full story in The Guardian.

The pioneering team was created last year amid pressure from activists, faith groups and experts to make Phoenix, Arizona, more livable.

New online mapping tool helps California prepare for extreme heat

Read the full story from UCLA.

As summer kicks off and California braces for more record-breaking temperatures, a new tool co-developed by UCLA researchers will help government officials, school administrators and communities visualize the neighborhoods most in danger from extreme heat. Low-income residents and communities of color are impacted most by hot weather, which is the deadliest effect of climate change in California.

HEAT.gov — National Integrated Heat Health Information System

Heat related illnesses and death are largely preventable with proper planning, education, and action. Heat.gov serves as the premier source of heat and health information for the nation to reduce the health, economic, and infrastructural impacts of extreme heat.