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Wildfires And Cancer Risk | Earth Wise

June 20, 2022 By EarthWise Leave a Comment

Hotter and drier conditions are leading to an increasing number of wildfires in North America and elsewhere around the globe. Scientists have linked the severe heat and drought that fuel these wildfires to climate change. As the climate continues to change, wildfires are projected to become more prevalent, more severe, and longer in duration.

According to a United Nations report released earlier this year, the Western U.S., northern Siberia, central India, and eastern Australia have already seen an uptick in wildfires. The likelihood of catastrophic wildfires globally could increase by a third by 2050 and more than 50% by the turn of the century.

According to a new study by researchers from McGill University, living near regions prone to wildfires may boost the risk of developing serious health issues. The study, which tracked more than two million Canadians over a period of 20 years, found a higher incidence of lung cancer and brain tumors in people exposed to wildfires. People living within 50 kilometers of wildfires during the past 10 years had a 10% higher incidence of brain tumors and a 4.9% higher incidence of lung cancer when compared to people living further away.

This study, which was recently published in The Lancet Planetary Health, is the first to examine how proximity to forest fires may influence cancer risk.

In addition to the impacts on air quality, wildfires also pollute aquatic, soil, and indoor environments. While some pollutants return to normal levels shortly after the fire, many others persist in the environment for long periods of time.

The research team notes that additional work is needed to develop more long-term estimates of the chronic health effects of wildfires.

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Exposure to wildfires increases risk of cancer

Climate change is causing more wildfires and governments are unprepared, says U.N.

Photo, posted August 17, 2020, courtesy of USFS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Atmosphere Is Thirstier | Earth Wise

May 9, 2022 By EarthWise Leave a Comment

The American West is in the throes of a two-decade-long drought. The climate there is getting warmer and drier, which has led to increasing demand for water resources from both humans and ecosystems. According to a new study by the Desert Research Institute and collaborators, the atmosphere across much of the U.S. is also demanding a greater share of water than it used to.

Evaporative demand, which is also called atmospheric thirst, is a measure of the potential loss of water from the earth’s surface up to the atmosphere. It is a function of temperature, humidity, wind speed, and solar radiation. The study, published in the Journal of Hydrometeorology, assessed trends in evaporative demand during a 40-year period from 1980-2020.

The study’s findings showed substantial increases in atmospheric thirst across much of the Western U.S. over that period, with the largest increases centered around the Rio Grande and Lower Colorado rivers. This is important because atmospheric thirst is a persistent force in pushing Western landscapes and water supplies toward drought.

The study found that, on average, increases in temperature were responsible for 57% of the changes observed in atmospheric thirst, humidity 26%, and the other factors playing lesser roles.

For farmers and other water users, increases in atmospheric thirst mean that, in the future, more water will be required to meet existing water needs. Crops already require more water than they did in the past and can be expected to require more water in the future. Over time, for every drop of precipitation that falls, less and less water is likely to drain into streams, wetlands, aquifers, or other water bodies.

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New study shows robust increases in atmospheric thirst across much of U.S. during past 40 years

Photo, posted August 9, 2007, courtesy of William Clifford via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving The Giant Sequoia | Earth Wise

April 22, 2021 By EarthWise Leave a Comment

Giant sequoia trees are some of the most remarkable living things on earth. They can live up to 3,000 years. The tallest specimens tower over 300 feet, but it is their girth that really sets them apart. They are usually 20 feet in diameter, and some are up to 35 feet across at the widest. The largest tree in the world by volume is the General Sherman tree, which has a volume of 52,508 cubic feet. At 2,100 years old, it weighs 2.7 million pounds and is not only the largest living tree, but also the largest living organism by volume on the planet.

Giant sequoias are incredibly hardy. To have survived thousands of years, the oldest of these trees have endured hungry animals, diseases, fires, snowstorms, El Niño events, years-long droughts, and the efforts of loggers during the 19th and 20th centuries.

In February, unusually high winds knocked down 15 giant sequoias in Yosemite National Park. While sequoias are amazingly adapted to their narrow range in California’s Western Sierras, it appears as though climate change is altering their habitat faster than the species can migrate or adapt. Shorter cold seasons have meant more rain instead of snow, leading to floods and mudslides in the winter. Fires are more likely with less snowpack. Hotter, drier summers put sequoias under greater stress.

Forest managers work to preserve existing groves through fire mitigation, supplementary water, and careful stewardship of young trees in existing groves. If these efforts are successful through the ensuing decades, climate change may be just one more thing the sequoias outlasted. But at least some conservationists are now considering planting a new generation of sequoias in colder, nearby habitats.

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To Save Giant Sequoia Trees, Maybe It’s Time to Plant Backups

Photo, posted June 8, 2008, courtesy of Joi Ito via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Forecasting A Bad Year For Carbon

March 11, 2019 By EarthWise Leave a Comment

Carbon dioxide levels in the atmosphere are higher than they have been for hundreds of thousands of years, and they continue to grow. The United Kingdom’s national meteorological service – known as the Met Office – issues annual predictions of global CO2 levels based in part on readings taken at the Mauna Loa observatory in Hawaii. Their forecast for this year is that there will be one of the largest rises in atmospheric carbon-dioxide concentration in the 62 years of measurements at Mauna Loa.

Since 1958, there has been a 30% increase in the concentration of carbon dioxide in the atmosphere. This has been caused by emissions from fossil fuels, deforestation and cement production. The increase would actually have been even larger if it were not for natural carbon sinks in the form of various ecosystems that soak up some of the excess CO2.

Weather patterns linked to year-by-year swings in Pacific Ocean temperatures are known to affect the uptake of carbon dioxide by land ecosystems. In years with a warmer tropical Pacific – such as El Niño years – many regions become warmer and drier, which limits the ability of plants to grow and to absorb CO2 . The opposite happens when the Pacific is cool, as was the case last year.

The Met Office predicts that the contribution of natural carbon sinks will be relatively weak, so the impact of human-caused emissions will be larger than last year. The predicted rise in atmospheric CO2 is 2.75 parts-per-million, which is among the highest rises on record. The forecast for the average carbon dioxide concentration is 411 ppm, with peak monthly averages reaching almost 415 ppm. With global emissions not really declining, the numbers just get higher and higher.

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Faster CO₂ rise expected in 2019

Photo, posted March 18, 2006, courtesy of Darin Marshall via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Disastrous Year

February 5, 2019 By EarthWise Leave a Comment

The number and economic impact of natural disasters around the world have increased dramatically over the past 30 years. In dollar terms, the amount has actually more than doubled. While 2017 and especially 2011 hold the records for worldwide economic damage, 2018 was pretty disastrous in its own right, totaling at least $160 billion.

The year was dominated by costly wildfires in California and tropical storms in the United States and Asia. According to a recent report by the reinsurance company Munich Re, the Camp and Woolsey fires in California alone caused losses of $21.7 billion, $16.5 billion of which was insured.

Overall, insurance companies paid out $80 billion in damage claims from natural disasters last year. This was less than the $140 billion in 2017 but is still double the 30-year average.

Losses from wildfires have increased dramatically in recent years and summers continue to get hotter and dryer, a likely consequence of climate change. These mounting costs bring into question whether people can continue to build in high-risk wildfire areas without dramatic changes in materials and the aggressive use of other protective measures.

Twenty-nine natural disaster events in 2018 caused more than a billion dollars in damage each. Tropical storms including hurricanes Michael and Florence in the United States and three Asian typhoons caused $57 billion in damage.

A severe drought in Europe that set off major wildfires and caused agricultural losses caused $3.9 billion in losses. Only about $280 million of this damage was covered by insurance companies since farmers in Europe don’t typically purchase insurance against drought. For them, 2018 was truly a disastrous year.

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Natural Disasters Caused $160 Billion in Damage in 2018

Photo, posted July 26, 2018, courtesy of Bureau of Land Management California via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Your Children’s Yellowstone

January 25, 2019 By EarthWise Leave a Comment

Yellowstone National Park was the first national park in the US and according to some sources, the first in the world. It is the home of charismatic megafauna and stunning geysers that attract over four million visitors a year. It is the only place in the United States where bison and wolves can be seen in great numbers. And it is changing.

Over the next few decades of climate change, Yellowstone will quite likely see increased fire, less forest, expanding grasslands, shallower, warmer waterways, and more invasive plants. All these things will alter how and how many animals move through the landscape. Ecosystems are always changing, but climate change is transforming habitats so quickly that many plants and animals may not be able to make the transition at all.

Since 1948, the average annual temperature in the Greater Yellowstone ecosystem has gone up by 2 degrees Fahrenheit. On balance, winter is 10 days shorter and less cold. The Northern Rockies snowpack has fallen to its lowest level in eight centuries. Summers in the park are warmer, drier, and increasingly prone to fire.

Non-nutritious invasive plants like cheatgrass and desert madwort have replaced nutritious native plants. When plants like these take over, they suck moisture out of the ground early so that bison and elk cannot be sustained throughout the summer.

The behavior of elk and other animals is already changing, with many staying outside the park to nibble lawns and alfalfa fields. In turn, wolves go where the elk go. Forests and waterways are changing as well.

The rapid changes going on at Yellowstone mean that the park that our children and grandchildren will visit in the future is likely to be a very different one from the Yellowstone we remember.

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In Yellowstone National Park, warming has brought rapid changes.

Photo, posted September 7, 2016, courtesy of Mike Yang via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Hawaii

December 18, 2017 By EarthWise Leave a Comment

The Hawaiian Islands are an archipelago of eight major islands, several atolls, numerous smaller islets, and seamounts in the North Pacific Ocean. The islands are a world-renowned vacation spot, known for their white-sand beaches, lush flora, and near perfect weather. But stormier days may be ahead.