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Methane From Thawing Permafrost | Earth Wise

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The Arctic permafrost contains a massive amount of carbon in the form of frozen soil, which contains remnants of plants and animals that died millennia ago.  Estimates are that there is 2 ½ times as much carbon trapped in this Arctic soil than there is in total in the atmosphere today.

As the Arctic warms, the permafrost is starting to thaw.  Once that happens, microbes begin to consume the previously frozen organic matter trapped in the soil.  As part of this process, the microbes produce large amounts of methane, which is an extremely potent greenhouse gas.   Thus, there continues to be great concern that wide-scale thawing of the permafrost would result in massive amounts of methane being released into the atmosphere.

A recent study in northern Sweden revealed a glimmer of hope.  The study gauged methane emissions from a swath of permafrost that thawed in the 1980s and another that thawed 10 or 15 years later. 

In the first area, as ice melted underground, water on the surface sank down into the soil.  As the surface dried out, new plants emerged that helped to keep methane emissions buried underground.

Grasses found in wet areas have straw-like structures that convey oxygen to their roots.  The straws also allow methane in the soil to escape into the atmosphere.  As the areas dry out, other plants lacking the straws can sometimes replace the grasses.  When methane can’t escape, soil bacteria break it down into carbon dioxide.

The result is that the permafrost releases only a tenth of the methane as expected.  The hope is that changes in plant cover driven by climate change may limit methane emissions from thawing permafrost.

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Thawing Permafrost In Sweden Releases Less Methane Than Feared, Study Finds

Photo, posted July 7, 2014, courtesy of NPS Climate Change Response via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Sleep | Earth Wise

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It’s no secret that our planet is heating up.  According to scientists, the warming is primarily the result of increased anthropogenic greenhouse gas emissions.  In fact, human activities are responsible for nearly all of the increase in atmospheric greenhouse gas emissions over the last 150 years. 

Climate change has already left observable effects on the planet.  For example, glaciers have shrunk, oceans have warmed, heatwaves have become more intense, and plant and animal ranges have shifted.

Most research examining the impact of climate change on human life has centered around extreme weather events and how they will affect social and economic health.  But climate change may also have a major influence on fundamental daily human activities, like sleep, that are essential to well-being.   

According to a new study recently published in the journal One Earth, scientists have found that increasing temperatures are negatively impacting human sleep around the globe.  In the study, the research team analyzed anonymized global sleep data from sleep-tracking wristbands.  The data included 7 million nightly sleep records from more than 47,000 adults across 68 countries, spanning all continents except Antarctica.     

Before the year 2100, researchers say that suboptimal temperatures may erode 50 to 58 hours of sleep per person per year.  On warm nights – where temperatures are greater than 86 degrees Fahrenheit – sleep declines an average of more than 14 minutes.  To little surprise, they found that the effect of increasing temperatures on sleep loss is substantially greater for residents in lower income countries as well as in older adults. 

Sleep is an essential restorative process integral to human health and productivity.  And it’s threatened by our changing climate. 

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Climate change likely to reduce the amount of sleep that people get per year

Photo, posted March 16, 2006, courtesy of Joe Green via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Antarctic Heatwave | Earth Wise

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The Concordia Research station atop Dome C on the Antarctic Plateau is generally considered to be the coldest place on earth.  In mid-March, the normal high temperature for the day is around -56 degrees Fahrenheit.  But on March 18, the high for the day was 11.3 degrees, nearly 70 degrees warmer than normal.

The World Meteorological Organization doesn’t formally track the metric of largest temperature excess above normal, but if it did, this would probably have set a world record.  Consider a place like Washington, DC.  Its normal high temperature on March 18 is 61 degrees.   Imagine if it got up to 131 degrees! 

The 11-degree reading at the Concordia Research Station was not only the record for the month of March.  It was actually the record for any month.

The Russian Vostok research station, which is another candidate for being the coldest place on earth based on its average high temperature, also saw some record high temperatures.  Vostok reported a high temperature of zero degrees Fahrenheit, which is 63 degrees above its average for the date.  It broke the station’s previous record by almost 27 degrees.

This record warming was the result of a unique combination of meteorological events that included a moist inflow of an atmospheric river as well as a rare infusion of hot air into the Antarctic plateau.  The arrival of the moisture in the atmospheric river trapped the hot air, allowing temperatures to shoot up.

The extreme warmth in Antarctica raises concerns about the long-term effects on the ice there.  A single short heatwave is not going to have a major effect, but if such events become more common, it could be real problem.

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Extraordinary Antarctica heatwave, 70 degrees above normal, would likely set a world record

Photo, posted October 15, 2016, courtesy of NASA Goddard Space Flight Center via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Historic Western Drought | Earth Wise

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The American Southwest has suffered from drought conditions since the year 2000.  The drought has reduced water supplies, devastated farmers and ranchers, and it has helped to fuel numerous wildfires across the region.  It has generally been considered to be worst in 500 years.

According to a recent analysis, the drought has become so severe that it has actually led to the driest two decades in at least 1,200 years and the changing climate is largely responsible.  The summer of 2021 was especially dry; about 2/3 of the West was in severe drought conditions.

Scientists at UCLA used tree ring data to gauge drought.  Based on that analysis, 2000-2021 is the driest 22-year period since 800 A.D. which is as far back as the data goes.

The study confirmed the role of temperature, more than precipitation, in driving exceptional droughts.  Precipitation levels can go up and down over time and can vary in different regions.  But the ongoing emissions of greenhouse gases into the atmosphere are causing temperatures to generally rise over time.  Warmer temperatures make the air more capable of pulling water out of the soil, out of vegetation, out of crops, and out of forests.  All of that makes drought conditions more severe.

A megadrought is generally considered to be one that is both severe and long.  But even during one, there can be wet years.  2005 was a notable one.  But there must be enough consecutive wet years to actually end a drought.

Several previous megadroughts over the past 1,200 years lasted as long as 30 years.  So, the current drought is in full swing and may go on for a long time to come.

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How Bad Is the Western Drought? Worst in 12 Centuries, Study Finds.

Photo, posted September 25, 2021, courtesy of David Sierralupe via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Is It Really Getting Warmer? | Earth Wise

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The primary indicator of global climate change is the Global Mean Surface Temperature of the Earth and the world’s nations are trying to keep its increase below 1.5 degrees Celsius over the pre-industrial level.   That rise in temperature is called the Global Surface Temperature Anomaly and it actually reached an all-time high in 2016 at 1.02 degrees before going back down.

At this point, you might be saying, “hold on there…  it hasn’t gotten larger over the past 5 years?”  What’s going on?

The global climate is pretty complicated and there are many things that influence it.  One of the most significant factors is the El Niño Southern Oscillation or, more familiarly, the El Niño.  The El Niño is a periodic and irregular variation in the sea surface temperature of the tropical eastern Pacific Ocean driven by persistent westerly winds.  When an El Niño is happening, currents move to the west coast of South America and warm the tropics and subtropics.  This causes a spike in the global mean temperature.  There was a strong El Niño in 2016.

On the other hand, when easterly winds dominate to form a La Niña, cool water comes up from the depths of the Pacific and cools the atmosphere.  In 2017 and 2018, there was a fairly strong La Niña, lowering the global mean temperature.  2020 had no El Niño or La Niña, and the global temperature went back up to its previous peak.  Last year, there was again a La Niña and the temperature dipped again.

The global mean surface temperature has been rising in the industrial era, but it also fluctuates with the complicated dynamics of the Pacific Ocean.

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Why Isn’t It Getting Warmer?

Photo, posted February 12, 2016, courtesy of Amit Patel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Permafrost Thaw | Earth Wise

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We’ve talked about permafrost before.  It is the frozen soil, rock, or sediment piled up in the Arctic that has been there at least for two years but, for the most part, for millennia or even over a million years.  Permafrost holds the carbon-filled remains of vegetation and animals that froze before they could start decomposing.   Estimates are that there are nearly 2,000 billion tons of carbon trapped in Arctic permafrost.  To put that in perspective, annual global carbon emissions are less than 40 billion tons.

Keeping all that carbon frozen plays a critical role in preventing the planet from rapidly heating. The ongoing warming of the Arctic is causing the subsurface ground to thaw and release long-held carbon to the atmosphere.

Scientists from Europe and the US are working together to better track permafrost carbon dynamics.  They are trying to understand the mechanisms that lead to abrupt thaws in the permafrost that have taken place in some locations.  These rapid thawing events are not well understood.  Researchers are also studying the effects of the increasingly frequent wildfires in the Arctic on the permafrost.

Researchers are using satellites to better understand the effects climate change is having on the Arctic environment and how these changes, in turn, are adding to the climate crisis.  Permafrost cannot be directly observed from space, so that its presence has to be inferred from measurements like land-surface temperature and soil moisture readings.  Terrestrial observations are also necessary for understanding how greenhouse gases – both CO2 and methane – are being emitted from the Arctic.

Thawing permafrost is a ticking timebomb for the environment that demands the growing attention of the scientific community.

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Permafrost thaw: it’s complicated

Photo, posted January 24, 2014, courtesy of Brandt Meixell / USGS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Beavers Are Flooding The Warming Arctic | Earth Wise

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The accelerating warming in the Arctic has transformed the region into a warmer, wetter, and more diverse environment.  Warming temperatures have encouraged the increasing growth of vegetation, particularly shrubs that provide beavers with bark to eat and branches to build with.  Warming temperatures also mean that lakes and streams freeze solid for shorter periods of time or not at all, allowing beavers to pursue their construction projects for longer periods during the year.

Prior to the mid-1970s, residents of the Alaskan Arctic encountered few beaver ponds.  In 2018, researchers using satellite imagery mapped 12,000 beaver ponds in Alaskan tundra.

Beavers are causing major changes in the streams and floodplains that many small Alaskan villages depend upon for food, water, and navigation.  As the rodents transform lowland tundra ecosystems, they are eliminating food sources, deteriorating water quality, and making it difficult to navigate waterways.

The migration of beavers across the Arctic landscape is largely a result of climate change.  But it is also becoming one of the factors amplifying climate change.  Scientists are trying to figure out the degree of permafrost thawing that beaver dam-and-den building is causing and how fast these defrosted organic soils will degrade and release trapped carbon and methane.

Beaver dams alter the hydrology of streams by slowing the flow, storing and spreading water to create wetlands, raising the water table, and lowering the oxygen content of the water. 

Climate-driven changes in species distributions affect human well-being as entire ecosystems continue to change.  Shifts in animal habitat stimulated by climate change could have profound consequences across the globe.

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Beavers Are Flooding the Warming Alaskan Arctic, Threatening Fish, Water and Indigenous Traditions

Photo, posted June 12, 2018, courtesy of Peter Pearsall/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And The World’s Fisheries | Earth Wise

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According to a new study, approximately 70% of the world’s oceans could be suffocating from a lack of oxygen by 2080 as a consequence of climate change.  This has the potential to impact marine ecosystems all around the world.  

The study, which was recently published in the journal Geophysical Research Letters, is the first to use climate models to predict how and when deoxygenation will occur throughout the world’s oceans outside of its natural variability. 

According to the findings, significant and potentially irreversible deoxygenation of the ocean’s middle depths began occurring last year.  The models predict that deoxygenation will begin affecting all zones of the ocean by 2080.

According to the study’s models, mid-ocean depths are already losing oxygen at unnatural rates. Globally, the ocean’s middle depth – known as the mesopelagic zone – is home to many of the world’s commercially fished species.  This makes these new findings a potential harbinger of economic hardship, seafood shortages, and environmental disruption. 

Just like land animals, aquatic animals need oxygen to breathe.  As climate change warms the oceans, the water holds less oxygen and is more buoyant than cooler water.  This leads to less mixing of oxygenated water near the surface with deeper waters, which naturally contain less oxygen.  Warmer water also raises oxygen demand among living organisms, resulting in less availability for marine life. 

The researchers also found that oceans closer to both the North Pole and the South Pole are particularly vulnerable to deoxygenation.  While they are not yet sure why, accelerated climate warming could be the culprit. 

These findings should add new urgency to climate change mitigation efforts. 

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Climate change has likely begun to suffocate the world’s fisheries

Photo, posted January 28, 2019, courtesy of Joseph Gage via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Antarctic Ice Collapse | Earth Wise

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In Antarctica, a huge chunk of the Larsen B Ice Shelf collapsed suddenly and spectacularly in January.

The Larsen Ice Shelf is located on the northeastern side of the Antarctic Peninsula on the Weddell Sea.  It was formed over the course of more than 12,000 years.  The Weddell Sea used to be a completely frozen body of water.  The famous Ernest Shackleton expedition in 1915 was trapped in its ice.  But the Antarctic Peninsula has been steadily warming in recent decades.

The Larsen A Ice shelf collapsed in 1995 and the 1,250-square-mile Larsen B Ice Shelf collapsed in 2002.  After that event, a portion of the detached ice shelf refroze in 2011 and was attached to the Scar Inlet Ice Shelf.  The refrozen ice was called the Larsen B embayment.

In January, the embayment broke apart, taking with it a portion of the Scar Inlet Ice Shelf.  It disintegrated within a matter of days.  The combined Larsen Ice Shelves – called A, B, C, and D – once extended along a 1000-mile stretch of the eastern Antarctic Peninsula.  Since 1995, it has shrunk from 33,000 square miles to 26,000 square miles.

These ice shelves float on the ocean, so their loss does not actually increase global sea levels.   However, the shelves act as dams that hold back glaciers located on the land behind them.  The loss of Antarctic ice shelves dramatically increases the rate at which glaciers flow into the sea, and that does increase global sea levels. 

Now that the sea ice from the Larsen B embayment is gone, it is likely that there will be additional inland ice losses from the newly exposed glaciers.

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Remnant of Antarctica’s Larsen B Ice Shelf Disintegrates

Photo, posted February 13, 2018, courtesy of NASA/Nathan Kurtz via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The All-Time Hottest Day | Earth Wise

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Last year saw record high temperatures in many places around the world and this year started out with more of the same.  In mid-January, Onslow, a small town in Western Australia, measured a high temperature of 123.3 degrees, tying the all-time highest temperature ever recorded anywhere in the Southern Hemisphere.  The previous reading was also made in Australia back in 1960.

The new temperature record was set just as climate institutions around the world were announcing that the past seven years have been the highest in recorded history.

The list of temperature records set in 2020 and 2021 is a long one.   2020 was the hottest year in recorded history.  July 2021 was the hottest month ever recorded.   The hottest official temperature ever recorded anywhere in the world was 129.9 degrees, occurring in Death Valley, California on both August 16, 2020, and July 9, 2021. 

The hottest temperature ever recorded in the Arctic was 100.4 degrees on June 20, 2020 in Verkhoyansk in Russia’s Sakha Republic.  (Amazingly, that small town also holds the record for the coldest temperature ever recorded in Asia at -90 degrees). 2021 saw an all-time high temperature recorded in Europe, in Syracuse, Sicily, on August 11 at 119.8 degrees. 

Overall, 400 documented weather stations in communities or outposts worldwide established all-time high temperatures in 2021 alone.  The climate we have lived through over the past decades is changing and these changes will have consequences to our way of life.

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Australia hits 123 degrees, tying hottest temperature on record in Southern Hemisphere

Photo, posted January 21, 2013, courtesy of A. Dombrowski via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And The Winter Olympics | Earth Wise

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According to a new study led by researchers from the University of Waterloo in Canada, climate change will limit where the Winter Olympics can be held as winter changes across the Northern Hemisphere. 

The international research team found that by the end of the century only one of the 21 cities that have previously hosted the Winter Olympics would be able to reliably provide fair and safe conditions for winter sports if global greenhouse gas emissions are not dramatically reduced. 

However, if the emissions targets set forth in the Paris Climate Agreement can be reached, the number of climate-reliable host cities for the Winter Olympics would jump to eight.

In the study, which was recently published in the journal Current Issues in Tourism, the researchers reviewed historical climate data from the 1920s to today, as well as future climate change scenarios for the 2050s and 2080s.  The researchers also surveyed international athletes and coaches, and found that 89% of them felt that changing weather patterns are already affecting competition conditions. 

The average February daytime temperature of host cities has been steadily increasing.  At the winter games held between the 1920s and 1950s, the average temperature was 32.7°F.  It rose to 37.6°F at games between the 1960s and 1990s, and has spiked to 43.3°F in the games held in the twenty-first century.  The planet is projected to warm another 3.6°F to 7.9°F this century depending on our ability to mitigate greenhouse gas emissions.

Reducing global greenhouse gas emissions is critical to ensure that there remain places across the globe to host the Winter Olympics.

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Climate change threatens future Winter Olympics

Photo, posted February 21, 2010, courtesy of Michael via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Melting Himalayan Glaciers | Earth Wise

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The great mountain ranges of central Asia, including the Himalayas, contain the third-largest deposit of ice and snow in the world, trailing only Antarctica and the Arctic.  The Himalayan range contains about 15,000 glaciers, and is part of a region widely referred to as the Third Pole due to its extraordinary reserves of freshwater.

But in recent years, scientists have observed an increase in the rate of Himalayan glacier loss.  According to a new study led by researchers from the University of Leeds in the UK, the accelerating melting of the Himalayan glaciers threatens the water supply of millions of people in Asia. 

In the study, researchers reconstructed the reach of the Himalayan glaciers during the Little Ice Age, which was the last major glacier expansion 400-700 years ago. They found that these glaciers began losing ice 10 times faster during the modern era.  In fact, the glaciers have shrunk from a peak of nearly 11,000 square miles to around 7,500 square miles today.   

This exceptional acceleration of melting of the Himalayan glaciers could have significant implications.  Hundreds of millions of people rely on Asia’s major river systems for food and energy, and depend on these glaciers to feed rivers during the dry seasons.  These rivers include the Brahmaputra, Ganges, and Indus.  The changing global climate could disastrously impact water resources and livelihoods of the Greater Himalayan region.

According to the research team, people living in these regions have already seen changes that are unlike anything witnessed for centuries.  This study is the latest to confirm that these changes are accelerating and pose a significant threat to entire nations and regions. 

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Himalayan glaciers melting at ‘exceptional rate’

Photo, posted March 13, 2018, courtesy of Sarunas Burdulis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Threat From Thwaites | Earth Wise

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The Thwaites Glacier in Antarctica is the widest glacier in the world. It is about 80 miles across and in places extends to a depth of about 2,600 to 3,900 feet.  The glacier is roughly the size of Florida, and it currently contributes 4% of annual global sea level rise as it continues to retreat from a warming ocean.

The International Thwaites Glacier Collaboration is a team of nearly 100 scientists dedicated to studying the glacier.  According to the scientists, Thwaites has doubled its outflow speed within the last 30 years.  The glacier in its entirety holds enough water to raise global sea levels by over two feet, which would be catastrophic.

A third of the glacier flows more slowly than the rest because it is braced by a floating ice shelf that is held in place by an underwater mountain.  The concern is that the brace of ice slowing the glacier may not last for long.

Beneath the surface, warmer ocean water is attacking the glacier from all angles.  The water is melting the ice directly beneath the glacier causing it to lose its grip on the underwater mountain.  Massive fractures have formed and are growing.

Warm water is also a threat for what is called the grounding zone, which is the area where the glacier lifts off the seabed. There are many possible scenarios under which there could be a major ice loss from the glacier.  It is unclear how quickly it could occur.  It might take decades, or it could be centuries.  The threat is large enough and real enough that continued observation and research is essential.

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The Threat from Thwaites: The Retreat of Antarctica’s Riskiest Glacier

Photo, posted October 16, 2012, courtesy of J. Yungel / NASA Ice via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fire And Ice | Earth Wise

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In recent years, there have been countless stories about the effects of the changing climate.  Many of those stories have been about the dwindling sea ice in the Arctic and many others have been about the worsening wildfires in the western United States.   According to a recent study published by the Pacific Northwest National Laboratory, those two things are very much related.

As sea ice in the Arctic melts from July to October, sunlight warms the surrounding land and sea surfaces.  The resulting differences in air pressure create and strengthens a vortex in the atmosphere above the heated area which spins counterclockwise like a cyclone.

The powerful vortex pushes the polar jet stream out of its typical pattern and diverts moist air away from the western United States.  With the jet stream moved off its usual course, a second vortex, this time spinning clockwise, forms under the ridge of the polar jet stream above the Western U.S.  This second vortex brings with it clear skies and dry conditions:  fire-favorable weather.

Arctic sea ice has continually declined at least since the late 1970s.  It is predicted that there will be periods of entirely iceless Arctic waters before the 2050s.  In turn, conditions in the already fire-ravaged West are likely to be further exacerbated.  More than three million acres have burned across California alone during the 2021 wildfire season.

Climate conditions in one part of the world can, over time, influence climate outcomes thousands of miles away.  The research at Pacific Northwest Laboratory reveals how regional land and sea surface warming caused by Arctic ice melting can trigger hotter and drier conditions in the West later in the year.

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Fire and Ice: The Puzzling Link Between Western Wildfires and Arctic Sea Ice

Photo, posted July 28, 2018, courtesy of Bob Dass via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Armadillos Heading North | Earth Wise

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Armadillos are small mammals known for their unique armor-like shell and their digging habits.  There are 21 species, primarily native to South America.  Some species have expanded northward due to their rapid breeding cycle, adaptability, and reduced number of predators.  Only one species – the nine-banded armadillo – is found in the United States.  In fact, it is the official small mammal of the state of Texas.

Over time, armadillos have expanded their range to states in the Deep South.  More recently, the animals have been pushing further north.  Milder winters in the changing climate have allowed them to inhabit new areas, including parts of the Blue Ridge Mountains. They were first sighted in North Carolina in 2007 and their numbers have recently been growing in the western half of the state.

There are now armadillos as far north as Missouri, Nebraska, and Iowa, and there is little to halt their further advance.  They are able to hold their breath for six minutes at a time, so they can cross rivers by walking along the bottom or by inflating their intestines and floating across the top.  Their hard shell provides protection from predators.  They reproduce prolifically.  Females give birth to quadruplets multiple times over the course of their 12-15-year lifespan.

Armadillos are fun to look at, but they are a nuisance where people live.  They are prone to digging holes in lawns.  In parts of North Carolina, some people have placed bounties on the animals.  They are difficult to trap and there aren’t common repellents for them.  As the climate continues to warm, it is only a matter of time before the range of armadillos expands into other states.

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Armadillos Advance Northward As Temperatures Rise

Photo, posted May 2, 2017, courtesy of Gail Hampshire via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Coral Reef Status Report | Earth Wise

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In October, the Global Coral Reef Monitoring Network released the first-ever report collecting global statistics on the world’s corals.  It documents the status of reefs across 12,000 sites in 73 countries over 40 years.  Overall, the news is not good, but there were some bright spots.

From 2009 to 2018, the world has lost 14% of its corals, corresponding to about 4,500 square miles of coral.  Global warming has led to prolonged marine heatwaves that trigger coral bleaching.  Local pollution has also damaged reefs.   The International Panel on Climate Change has reported that 2 degrees Celsius of global warming would wipe out 99% of the world’s corals.

The report does show that corals can recover globally if given a decade of cooler waters.  Some places in the world – particularly the Coral Triangle in Asia, which contains nearly a third of the world’s coral – have actually seen coral growth over the past decade. 

The Global Coral Reef Monitoring network started collecting data in 1978.  Coral health was fairly steady until 1998 when the first mass bleaching event occurred, triggered by a powerful El Niño event.  For the next 12 years, corals recovered nicely, but then bleaching events in 2010 and 2015-17 took their toll.

The Pacific, Australia, and the Caribbean have all seen major decreases in coral.  The Coral Triangle is a major exception which is thought to be a result of genetic diversity among the region’s corals.

Coral conservationists globally are working to protect corals and to actively restore them.  The situation is fairly dire, but there continue to be reasons for hope.

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Finding Bright Spots in the Global Coral Reef Catastrophe

Photo, posted October 13, 2015, courtesy of Albert Straub via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

How Quickly Can The Planet Recover? | Earth Wise

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Climate change refers to long-term shifts in temperatures and weather patterns.  Historically, these shifts were natural.  But since the Industrial Revolution, scientists have found that the main driver of climate change has been human activities, primarily by adding significant amounts of greenhouse gases into the atmosphere through the burning of fossil fuels. 

Today, climate change is destabilizing Earth’s temperature equilibrium and is having a widespread impact on humans, animals, and the environment.  Some of the consequences of anthropogenic climate change include warmer air and ocean temperatures, shrinking glaciers, increasing spread of pests and pathogens, declining biodiversity, and more intense and frequent extreme weather events. 

But how quickly can the climate recover from the warming caused by an increase in carbon dioxide in the atmosphere? 

Researchers from Johannes Gutenberg-University Mainz in Germany looked into this question by investigating the significant rise in global temperatures that took place 56 million years ago.  Likely triggered by a volcanic eruption,  the increase of between 5 and 8 degrees Celsius was the fastest natural period of global warming that has impacted the climate. 

Because higher temperatures cause rocks to weather faster, the research team decided to analyze the weathering processes that occurred during the warming event 56 million years ago.  Their findings, which were recently published in the Journal Science Advances, indicate that the climate took between 20,000 and 50,000 years to stabilize following the rise in global temperatures.

Climate change is not some distant problem.  It is happening now and it poses a serious threat to all forms of life.  We need to address the problem with more urgency. 

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How quickly does the climate recover?

Photo, posted August 27, 2017, courtesy of Lt. Zachary West (100th MPAD) / Texas Military Department via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Deadly Urban Heat On The Rise | Earth Wise

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According to a new study by the Columbia Climate School, exposure to deadly urban heat has tripled since the 1980s.  The increase is the combined result of both rising global temperatures and booming urban population growth.

The study looked at more than 13,000 cities worldwide and found that incidents of extreme heat and humidity have increased dramatically.   It defined extreme heat as 30 degrees Celsius on the wet-bulb temperature scale that takes into account the effect of high humidity.  In 1983, there were 40 billion person-days under such conditions.  By 2016, the number was 119 billion.  More specifically, in 2016 1.7 billion people were subjected to such conditions on multiple days.

Sheer urban population growth accounted for two-thirds of the increase, while actual warming contributed a third.  Over recent decades, hundreds of millions of people have moved from rural areas to cities, which now hold more than half the world’s population.  And because of the urban heat island effect, temperatures in cities are generally higher than in the countryside.

In the United States, about 40 sizable cities have seen rapidly growing exposure to extreme heat, mainly clustered in Texas and the Gulf Coast.  Globally, nearly a quarter of the world’s population is affected by the increased incidence of extreme temperatures.

A study last year showed that combinations of heat and humidity literally beyond the limits of outdoor human survival have been popping up around the world.  A wet-bulb temperature reading of 30 – equivalent to 106 degrees Fahrenheit on the “real feel” heat index – is the point at which even most healthy people find it hard to function outside for long, and the unhealthy might become very ill or even die.

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Exposure to Deadly Urban Heat Worldwide Has Tripled in Recent Decades, Says Study

Photo, posted March 5, 2007, courtesy of Michael Phillips via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Earth Is Dimming | Earth Wise

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According to a new study published in the journal Geophysical Research Letters, warming ocean waters have caused a drop in the brightness of the earth.

Researchers measure the earth’s albedo by observing the light reflected from earth that illuminates the surface of the moon as well as with satellite measurements. The earth reflects about 30% of the sunlight that shines on it.  The data shows that the earth now reflects about half a percent less light than it did 20 years ago, with most of the drop occurring in the last three years.  That number had been fairly constant for most of the past 20 years.

According to the researchers at the New Jersey Institute of Technology, New York University, and a Spanish astrophysical agency, the apparent cause of the albedo drop has been a reduction of bright, reflective low-lying clouds over the eastern Pacific Ocean in most recent years.  That is the same area off the west coasts of North and South America where increases in sea surface temperature have been observed because of the reversal of a climate condition called the Pacific Decadal Oscillation, which is likely a result of global climate change.

The dimming of the earth implies that more solar energy is being absorbed rather than reflected, which may contribute further to global warming.

These results are somewhat surprising.  Scientists had postulated that the warming of the earth could lead to more clouds and therefore a higher albedo – more reflection of the sun’s light.  If that were the case, it would help to moderate warming and balance the climate system.  These new results indicate that the opposite is true.

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The Earth Is Dimming Due To Climate Change

Photo, posted August 18, 2021, courtesy of Arek Socha/GPA Photo Archive via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Right Whales And The Warming Atlantic | Earth Wise

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The warming of the Atlantic Ocean has driven the critically endangered North Atlantic right whale population from its traditional and protected habitat.  This has exposed the whales to more lethal ship collisions, increased entanglements with commercial fishing gear, and greatly reduced calving rates.

Since 2010, the calving rate has declined, and the right whale population has dropped by an estimated 26%.  Ten years ago, there were about 500 North Atlantic right whales; now there are an estimated 356.

These are some of the best studied whales in the oceans; scientists basically recognize each individual whale and when they are the victims of ship collisions or fishing entanglements, it is easy to identify which animal was killed.

Because of the warming climate, the Atlantic Meridian Overturning Circulation – an important system of surface and deep currents – has slowed down, causing the Gulf Stream to move north.  This has injected warmer and saltier water into the Gulf of Maine.  The warming Gulf of Maine has reduced the abundance of copepods, tiny crustations that are the favorite snack of right whales.   This has reduced whale calving rates and forced the whales to move north to the cooler waters of the Gulf of St. Lawrence.

For the past 6 years, more and more right whales have been observed feeding in the Gulf of St. Lawrence, where there were no protections in place to prevent ship strikes and fishing gear entanglement.  In 2017 alone, 17 right whale deaths were confirmed.

According to a recent report from Cornell University and the University of South Carolina, unless its management is improved, right whale populations will decline and potentially become extinct in the coming decades.

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Warming Atlantic forces whales into new habitats, danger

Photo, posted December 8, 2016, courtesy of Sea to Shore Alliance/NOAA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

WAMC Northeast Public Radio

WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)