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New Orleans is sinking

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As climate change accelerates, rising sea levels are putting coastal communities at greater risk of flooding and storm surge. Driven by melting glaciers and warming oceans, global sea levels are rising at an increasing rate. For low-lying cities like New Orleans, even small increases can have serious consequences. And that risk is compounded by another factor: the land itself is sinking.

Much of New Orleans already sits at or below sea level, and parts of the city and its surrounding wetlands are gradually sinking. While most of the city remains stable, a new study by researchers from Tulane University suggests that sections of the region’s $15 billion post-Katrina flood protection system may require ongoing upgrades to keep pace with long-term subsidence.

The study, recently published in the journal Science Advances, used satellite data to track changes in ground elevation across Greater New Orleans between 2002-2020.  The researchers found that some areas – including neighborhoods, wetlands, and even concrete floodwalls – are sinking by more than an inch each year. In some spots, the land is dropping by nearly two inches annually.

Alarmingly, some of the concrete floodwalls and levees built to protect the city after Hurricane Katrina are themselves sinking. In a few cases, they are losing elevation faster than sea levels are rising, reducing their capacity to block storm surges.

The study highlights how satellite monitoring can play a critical role in guiding infrastructure maintenance and urban planning – not just in New Orleans – but in vulnerable coastal cities around the world.

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Vertical land motion in Greater New Orleans: Insights into underlying drivers and impact to flood protection infrastructure

Photo, posted September 22, 2010, courtesy of U.S. Army Corps of Engineers via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Tracking emissions by satellite

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Carbon dioxide and nitrogen oxides are two of the most problematic human-generated air pollutants that negatively impact air quality, the climate, and human health.  Satellites are an important tool for monitoring emissions of these pollutants, but they have limitations.  For the most part, satellites have limited spatial resolution, meaning that they can’t reliably narrow down the source of emissions sufficiently to pin down a specific location such as a power plant. 

Until now, there have been no instruments that can detect both carbon dioxide and nitrogen oxide simultaneously with high spatial resolution.  Often just nitrogen oxide measurements are made, and carbon dioxide levels estimated based on the fact that both are emitted together with typical ratios.

A German research team from the Max Planck Institute and the Heidelberg Institute have developed a technology for the EnMAP environmental satellite to detect both gases with an unprecedented spatial resolution of 30 meters.  Data from the satellite makes it possible to track multiple sources of emission plumes over several tens of kilometers.

The EnMAP system was originally designed for remote sensing of land surfaces.  The new research demonstrates that reliable measurements of trace gases are possible even with an instrument not specifically designed for atmospheric observations.  When using it, it’s possible to determine the distribution of carbon dioxide and nitrogen oxide in emission plumes from individual power plants.  The ability to measure both gases individually means that conclusions can be drawn about the technology, efficiency, and operating mode of the systems being measured.

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German satellite measures CO2 and NO2 simultaneously from power plant emissions for the first time

Photo, posted September 19, 2020, courtesy of Sandor Somkuti via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Volcano monitoring

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Researchers at the University of Alaska Fairbanks and the U.S. Geological Survey have developed a radar-based volcano monitoring system.  The purpose is to provide situational awareness of volcano behavior and identify volcanoes that are becoming restless before other more obvious indications like earthquake activity occur.

The system is called VolcSARvatory and makes use of interferometric synthetic aperture radar to detect ground movement changes as small as one centimeter.  It utilizes two or more radar images from satellites taken at different times.  The images are used to create a time series of data from a single location.

The system has been in operation since early 2022 and proved to be valuable in studying the unexpected activity at the long-quiet Mount Edgecumbe volcano near Sitka, Alaska where conventional monitoring was not taking place.

According to the researchers, the technology has evolved to the point where it can be operational at a national level.  The goal is to provide a consistent approach to monitoring active volcanoes.

Volcanoes are not a rare and unlikely source of potential danger in this country.  The volcanoes of Hawaii are the best-known active volcanoes in the United States, but Alaska has about 140 volcanoes that are technically classified as active, with more than 50 that have been active within the past 300 years.  In total, 169 U.S. volcanoes are classified as active including ones in Arizona, California, Colorado, Idaho, Nevada, New Mexico, Oregon, Utah, Washington and Wyoming.

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Alaska-developed volcano monitoring system will expand across U.S.

Photo, posted March 18, 2013, courtesy of Jeffrey Wickett / USFS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Rising seas are destroying buildings

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Alexandria is the second largest city in Egypt and is the largest city on the Mediterranean coast.  Its history goes back over 2,300 years and it was once home to a lighthouse that was among the Seven Wonders of the Ancient World and a Great Library that was the largest in the ancient world.  The modern city has more than 6 million residents but still has many historic buildings and ancient monuments.  But perhaps not for long.

Rising seas and intensifying storms are taking a toll on the ancient port city.  For centuries, Alexandria’s historic structures have endured earthquakes, storm surges, tsunamis, and more.  They are truly marvels of resilient engineering.  But now, climate change is undoing in decades what took millennia for humans to create.

Over the past two decades, the number of buildings collapsing in Alexandria has risen tenfold.   Buildings are collapsing from the bottom up as a rising water table weakens soil and erodes foundations.  Since 2001, Alexandria has seen 290 buildings collapse.  Comparing present-day satellite imagery with decades-old maps, the authors of a study by the Technical University of Munich have tracked the retreat of Alexandria’s shorelines to determine where seas have intruded into groundwater. The authors say that more than 7,000 buildings in Alexandria are at risk.  They call for building sand dunes and planting trees along the coast to block encroaching seawater.

The true cost of this gradual destruction goes far beyond bricks and mortar.  This is the gradual disappearance of historic coastal cities.  Alexandria is a warning for such cities around the world.

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In This Storied Egyptian City, Rising Seas are Causing Buildings to Crumble

Photo, posted September 11, 2012, courtesy of Sowr via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The human footprint on Earth

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The Earth is a pretty big place, and it is easy to think that humans and their activities occupy very little of it.  But the impact of human activities on our planet continues to grow.  Recent satellite images from NASA’s Earth Observatory show the staggering extent of the human footprint on Earth.

Agriculture is a major part of it.  Farms and pastures take up almost half of the world’s habitable land – land not covered by ice or desert.  Greenhouses have recently proliferated tremendously and now cover 3.2 million acres, an area the size of Connecticut, and they even have effects on local climates.

More than half of the world’s population now lives in cities, which are expanding rapidly.  Enormous cities in Asia are changing the landscape in places like Thailand and Indonesia.  Apart from taking up lots of land, many of the world’s cities are immersed in clouds of air pollution that they generate.

Greenhouse gas emissions continue to grow, and temperatures continue to rise.  The effects of this on the planet are increasingly evident.  Seas are rising, ice is melting, glaciers shrink away, and wildfires continue to burn.  The massive wildfires in and around Los Angeles have made major changes in the local landscape.  Rising seas have flooded coastal wetlands and elsewhere, rivers and lakes have shrunk.

There are also human impacts visible from space that represent positive signs.  Large solar arrays supply the cheapest form of energy in most parts of the world and the number and size of solar installations are at a record high.   These solar installations provide some hope that global warming can be slowed.

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The Growing Human Footprint on Earth, as Seen from Space

Photo, posted July 28, 2012, courtesy of Beth Scupham via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Dangers of distant fires

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Smoke from wildfires is well known to exacerbate health problems like heart disease, lung conditions, and asthma.  People living in the vicinity of where fires occur face these dangers.  But a new study at the University of Maryland has found that there are health impacts from wildfires occurring thousands of miles away.

During the summer of 2023, massive Canadian wildfires created a vast plume of smoke that drifted more than 2,000 miles across the country resulting in poor air quality across the entire East Coast of the U.S. 

Baltimore had very dark skies over a six-day period in June 2023, sending many individuals to doctors’ offices complaining of breathing issues.  University of Maryland researchers found that medical visits for heart and lung problems rose by nearly 20% during that period.

Using satellite and EPA data combined with electronic health records, the researchers found increased likelihood of patients going to the doctor for complications related to cardiopulmonary conditions during the days with the most smoke in the air.  They found a 55% increase in the risk for an outpatient visit for heart and lung conditions and these additional patients tended to be older, non-smokers, and more socio-economically affluent than the typical patients who see their doctors for such conditions when the air quality is good.

With more climate-related events likely to occur in the future, doctors may require better tools to help disadvantaged patients on so-called hotspot days when conditions are most dangerous.  Increasingly common wildfires are a particular danger to people even when those fires are far away from where they live.

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Exposure to Remote Wildfire Smoke Drifting Across the U.S. Linked to Increased Medical Visits for Heart and Lung Problems

Photo, posted June 8, 2023, courtesy of Marc A. Hermann / MTA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Antarctic greening

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The Antarctic Peninsula, like other polar regions, is warming faster than the rest of the world.  Ocean heatwaves and ice loss are becoming more common and more severe.

New research by the universities of Exeter and Hertfordshire in the UK along with the British Antarctic Survey used satellite data to assess how much the Antarctic Peninsula has been greening in response to climate change.  The Antarctic Peninsula is an 800-mile extension of Antarctica toward the southern tip of South America.

The study found that the area of vegetation cover across the Peninsula increased from less than one square kilometer in 1986 to almost 12 square kilometers in 2021.  This greening trend accelerated by more than 30% in the period 2016-2021 relative to the entire 1986-2021 period.

An earlier study also showed that the rates of plant growth on the Antarctic Peninsula has increased dramatically in recent decades.  The landscape is almost entirely dominated by snow, ice, and rock, with only a tiny fraction supporting plant life.  The plants found on the Peninsula – mostly mosses – grow in some of the harshest conditions on earth.  But that tiny fraction has greatly increased, showing that this isolated wilderness is being altered by climate change. 

The sensitivity of the Antarctic Peninsula’s vegetation to the changing climate is evident and as warming continues, there could be fundamental changes to the biology and landscape of this unique and vulnerable region.

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Antarctic ‘greening’ at dramatic rate

Photo, posted June 2, 2018, courtesy of Murray Foubister via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Greenhouses and the environment

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The use of greenhouses around the world has been growing dramatically.  A new satellite mapping exercise estimated the total land area covered with permanent greenhouses at 3.2 million acres, which is an area the size of Connecticut.  More than half of this is in China, where the growth of greenhouses has been driven by the rapid urbanization of the country and by a more prosperous population increasingly consuming produce like tomatoes, cucumbers, peppers, and eggplants.

The intensive agricultural methods employed within greenhouses can be harmful to local environments because of overtaxing water supplies and by polluting rivers and soils with nutrients, pesticides, and plastic waste.  But the effects of vast areas of plastic coverings on local temperatures can be even more dramatic, and often beneficial.

There are so many plastic and glass roofs in many areas that they are reflecting sufficient amounts of solar radiation to cool local temperatures.  Greenhouse roofs increase the albedo – the reflectivity – of the land surface typically by a tenth.

All these greenhouses are just the tip of the albedo iceberg.  Many farms now temporarily cover crops with reflective plastic sheets.  If these coverings are included in the satellite survey, the total reflective area would be about ten times greater – roughly the size of New York State.

A study in Almeria, on the Mediterranean coast of Spain, which grows about 3 million tons of fruit and vegetables annually, determined the cooling effects of greenhouses.  Weather stations amid the greenhouses showed an average cooling of 1.3 degrees Fahrenheit compared with the surrounding area.

Greenhouses are an accidental and benign form of climate engineering. The cooling provided by greenhouses is similar to the effect of white roofs in urban areas. 

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Could the Global Boom in Greenhouses Help Cool the Planet?

Photo, posted September 6, 2017, courtesy of Lance Cheung / USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Penguin detectives

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Emperor penguins, the tallest and heaviest of all living penguins, are also the most famous, being the subject of a very popular documentary film.  The ongoing loss of sea ice in Antarctica has led to unprecedented breeding failures in emperor penguin colonies. 

Since 2016, Antarctica has seen the four years with the lowest sea ice extent on record.  Between 2018 and 2022, 30% of the 62 known emperor penguin colonies were affected by partial or total sea ice loss.  Current predictions suggest that the population of emperor penguins will fall by 99% by the end of the century.

To monitor remote emperor penguin colonies, researchers use satellite images in which the brown stains of the birds’ guano stand out against the white ice and snow.

Researchers at the British Antarctic Survey have launched the ‘Polar Observatory’ on the online citizen science website Zooniverse to recruit ‘penguin detectives’ to help validate the accuracy of satellite images in assessing penguin populations.

The online app contains drone photos taken over the Snow Hill penguin colony.  The images have been split into more than 300 10-meter squares.  Volunteers are asked to identify any adult and chick penguins in a given picture.  The results will be fed into machine learning algorithms to train the AI systems in automatically counting penguins in future surveys.

The project is a fun opportunity for aspiring conservationists and penguin lovers in general to help learn more about the future of the species.  Interested people can learn more on the Zooniverse website.

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‘Penguin detectives’ required for new counting app

Polar Observatory

Photo, posted October 7, 2017, courtesy of Christopher Michel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The East Coast is sinking

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Most of the world’s largest cities are located in coastal regions and coastal regions are on the front lines of the climate crisis.  Human populations continue to migrate towards low-elevation coastal areas at the same time that sea level rise is accelerating.  Coastal communities worldwide are increasingly vulnerable to the dangers of flooding and erosion.  With these hazards occupying a great deal of attention, there has been less attention paid to the dangers of land subsidence.

A recent study by researchers at Virginia Tech and the US Geological Survey using satellite data shows that parts of America’s east coast are sinking, and the culprit is the withdrawal of too much water from the aquifers beneath these coastal areas.

A series of overlapping aquifers extends all the way from New Jersey to Florida along the coast, providing a reliable source of water for drinking, irrigation, and industrial uses.  Even though these areas get regular rainfall, the deeper aquifers can take hundreds or even thousands of years to refill once water is pumped out.  Once water is removed, soils can compress and collapse, causing the land surface to sink.

Cities that were built on drained marshland or on fill soil are especially vulnerable to compaction. 

Seal level rise is slow, but it is insidious and continuous.  Add land subsidence to the mix and effects multiply.  Places like Boston, New York, Washington DC, Roanoke, Savannah, Jacksonville, and Miami, among others, all are increasingly vulnerable to these coastal hazards.  The combined effects of sea level rise and subsidence may even triple the prospects for flooding areas over the next few decades.

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As Aquifers Are Depleted, Areas Along The East Coast Of The US Are Sinking

Photo, posted August 7, 2015, courtesy of Tracy Robillard / NRCS Oregon via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Lakes Are Shrinking | Earth Wise

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A study by the University of Colorado Boulder has found that more than half of the world’s largest lakes have shrunk over the last three decades.  This is a very big problem because about one-quarter of the Earth’s population lives in the basin of a drying lake.  People depend on lakes for drinking water and irrigation and lakes are central to the survival of local ecosystems as well as migrating birds.  Lakes cover only about 3% of the planet, but they hold nearly 90% of the liquid surface freshwater.

The study used satellite observations from 1992 to 2020 to estimate the area and water levels of nearly 2,000 freshwater bodies.  These account for 96% of Earth’s total natural lake storage and 83% of that in man-made reservoirs.  About 53% of the world’s lakes have clearly shrunk, while only 22% have gained water.  The study estimates that about 160 trillion gallons of water has been lost over the 28-year period.  That’s about 17 times the maximum capacity of Lake Mead, the largest reservoir in the United States.

Many of the world’s most significant lakes have been shrinking. The dramatic declines in Lake Mead have been headline news for years.  The Caspian Sea, which is the world’s largest inland body of water – has long been declining.

The main causes of the decline in natural lakes are climate change and human consumption.  Reservoirs face an additional major problem of sediment buildup which reduces their storage capacity and diminishes their benefits of water supply, flood control, and hydropower.

Lake loss is a big problem.

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More than half of the world’s largest lakes are drying up

Photo, posted April 10, 2018, courtesy of Ninara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Upper Atmosphere Is Cooling | Earth Wise

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The part of the atmosphere closest to the Earth’s surface has been warming since the Industrial Revolution.  This warming is associated with increasing amounts of carbon dioxide as well as other human-made chemicals that have been changing the makeup of the atmosphere. Climate change is generally thought about in terms of the lowest regions of the atmosphere – known as the troposphere – where our weather happens.

But climate models also predict that another result of the changes to the makeup of the atmosphere is that most of the atmosphere up higher will get dramatically colder.  The same gases that are warming the bottom few miles of air are cooling the much greater expanses above that extend to the edge of space.

Recent satellite data has confirmed the accuracy of these models and provide further confirmation of the human fingerprint of climate change. The natural variability of weather that complicates climate models does not play a role in the upper atmosphere.

In the higher levels of the atmosphere, the effects of increasing levels of carbon dioxide are quite different.  In the thinner air up there, the heat trapped and re-emitted by CO2 does not bump into other molecules creating warming.  Instead, it escapes to space.  Combined with the trapping of heat at lower levels, the result is a rapid cooling of the upper atmosphere.

There are potential problems associated with the cooling upper atmosphere including that it is contracting.  The result is that the crowd of manmade objects in low orbit remains there longer, and there is a potential increased degradation of the ozone layer. 

The changes we are making to the atmosphere are having significant effects from the surface of the earth to the edge of space.

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The Upper Atmosphere Is Cooling, Prompting New Climate Concerns

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

Earth Wise is a production of WAMC Northeast Public Radio

Counting Trees | Earth Wise

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Scientists estimate that there are about 3 trillion trees on the earth.  A huge number but probably half as many as there were before people entered the picture.  And we’re losing about 10 billion trees a year to toilet paper, timber, farmland expansion, and other human activity.  Trees play a crucial role in taking carbon dioxide out of the atmosphere and storing it away.  For this reason, trees have become an integral part of the effort to mitigate climate change.

There are major initiatives underway around the world to plant more trees.  Part of this is driven by the increasing use of carbon credits by companies trying to offset their carbon emissions.   These credits are earned by either planting new trees or paying farmers or other landowners not to cut down existing trees.  But how many trees are actually planted and how many survive over time?

Whether these efforts are really resulting in more trees and more carbon storage is not easy to determine.  Current international inventories of global tree-sequestered carbon are subject to great uncertainty.

Researchers from the University of Copenhagen and NASA have developed a method for mapping large numbers of trees and determining their carbon content.  Using artificial intelligence techniques to analyze ultra-high-resolution satellite images, they can count trees, determine their individual species, and measure their carbon content.

A study of images from Africa’s Sahel region found that it is home to nearly 10 billion trees that are currently storing 840 million tons of carbon.

Now that the groundwork for this new methodology is complete, it is ready to be deployed by public agencies, NGOs, and other interested in monitoring the numbers of trees and their carbon content.

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The counting of nine billion trees could help manage climate credits and nature restoration

Photo, posted October 27, 2018, courtesy of Ian Dick via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Record Low Antarctic Sea Ice | Earth Wise

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Recent satellite observations of the sea ice in the Antarctic found the lowest level of ice cover ever seen in the forty years that these observations have been made.  As of February 8th, there were only 849,000 square miles of the Southern Ocean covered with ice.  The previous record low was measured last February 24th when the total coverage was 876,000 square miles.  Ice melting was likely to continue as the month went on.

This past January had already set a new record for that month’s mean extent of ice coverage at 1.24 million square miles. This rapid decline in sea ice has been going on for the past six years and is very unusual.  Average Antarctic ice cover hardly changed at all during the previous thirty-five years.

Antarctic sea ice generally reaches its maximum extent in September or October and its minimum extent in February.  At its maximum, the sea ice cover in the Antarctic is generally between 6.9 and 7.7 million square miles.   On the other hand, there are some places where the sea ice melts completely during the Southern Hemisphere summer.  Sea ice varies much more in the Antarctic than in the Arctic where the ice is much thicker.

Climate warming at the poles is much higher than at lower latitudes.  Nonetheless, it is not yet clear whether what we are seeing is the beginning of the end of summer sea ice in the Antarctic, or whether this is just a new phase characterized by low but still stable sea ice cover in the summer.

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Record low sea ice cover in the Antarctic

Photo, posted January 24, 2012, courtesy of Rob Oo 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.

People And The Earth’s Increasing Heat | Earth Wise

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A new study by Princeton University and the National Oceanic and Atmospheric Administration had found clear evidence that human activity is the primary cause of the significant increase in heat stored in our planet.  In fact, the study found that there is less than a 1% chance that natural variability is the sole cause of the increase.

The researchers looked at data from satellite observations to determine the amount of energy received by the earth and the amount reflected and emitted by the Earth.  In a balanced physical system, the amount of incoming energy should equal the amount of outgoing energy.  But the earth’s system is not balanced at this point.  More energy is coming in than going out, which is driving changes in the climate system.  There have been other studies looking at the human influence on the climate, but this new study is the first to examine a 20-year continuous satellite energy balance record to see if natural fluctuations in the climate system or human activities is the primary driver for the significant change in the planet’s energy balance.

The study examined 50 different climate models to look at this energy balance under scenarios where there was no human influence.  These include changes in the sun’s output, volcanic eruptions, variations in pollution aerosols, and more.

The results, to no great surprise, are that increasing greenhouse gases over the last twenty years is by far the most important driver for the energy imbalance.  This imbalance is what is driving rising temperatures, increasing sea levels, and causing other climate changes.

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Human activities responsible for rapid increase in Earth’s heat

Photo, posted May 6, 2021, courtesy of Marlis Borger via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Giant Breakaway Iceberg | Earth Wise

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Scientists have been closely monitoring multiple cracks and chasms that have formed in the 500-foot-thick Brunt Ice Shelf in Antarctica over the past few years.  In late 2019, a new crack was spotted in a portion of the shelf north of an area known as the McDonald Ice Rumples.  The rift was monitored by satellite imaging and was seen by February as moving about 15 feet a day.

In the early hours of February 26th, the crack widened rapidly before finally breaking free from the rest of the floating ice shelf.  News reports around the world have described the massive 500-square-mile iceberg by comparing it to the size of well-known cities:  1.5 times the size of greater Paris, 10 times the size of San Francisco, twice the size of Chicago, nearly the size of Greater London, and so on.

Antarctica is known for churning out some enormous bergs.  The new iceberg, which has been named A-74, is huge, but doesn’t compare to the iceberg A-68 that calved from the Larson C Ice Shelf in 2017.  That one was almost five times larger.

The calving of A-74 does not pose a threat to the presently unmanned British Antarctic Survey’s Halley VI Research Station, which was repositioned in 2017 to a more secure location after the ice shelf was deemed to be unsafe.  The section where the station now sits is still holding on, but when it eventually breaks, it will likely create a berg nearly 700 square miles in size.

It remains to be seen what will become of the new iceberg.  Most likely, it will eventually get caught up in the Weddell Gyre, a clockwise-rotating ocean flow in the Southern Ocean that covers an area more than half the size of the US.

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Breakup at Brunt

Photo, posted October 27, 2016, courtesy of NASA/Nathan Kurtz via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Collapse of Northern California Kelp Forests | Earth Wise

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For thousands of years, thick canopies of kelp formed an underwater forest spanning the coast of Northern California.  Kelp is the cornerstone of a rich subtidal community, providing food and habitat for all sorts of marine creatures.  But in recent years, a shocking transformation has occurred.  Satellite imagery reveals that the area covered by kelp forests off the coast of Northern California has declined by more than 95%.  Only a few small, isolated patches remain.  

In a new study, researchers at the University of California Santa Cruz found that the kelp forest decline was an abrupt collapse as opposed to a gradual decline. 

According to the study, which was recently published in the journal Communications Biology, kelp forests north of San Francisco were resilient to warming events in the past, like El Niños and marine heatwaves. But the decline of a key sea urchin predator – the sunflower sea star – from sea star wasting disease caused the kelp forests’ resiliency to plummet.  Sea urchins are voracious consumers of kelp.     

But it was a series of events – not just the sea urchins – that combined to decimate the Northern California kelp forest.   A marine heatwave that became known as “the blob” developed in 2014 and moved down the West Coast in 2015.  Around the same time, a strong El Niño event developed and brought warmer water up the coast from the south.  The warming ocean waters combined with the ravenous sea urchin population resulted in the dramatic decline of kelp. 

According to researchers, the prospects for a Northern California kelp forest recovery remain poor unless sea urchin predators return to the ecosystem. 

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The collapse of Northern California kelp forests will be hard to reverse

Photo, posted August 13, 2019, courtesy of Sara Hamilton of OSU College of Science via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The First Earth Fund Awards | Earth Wise

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Last February, Amazon CEO Jeff Bezos announced that he was launching the Bezos Earth Fund that would grant money to scientists, activists, NGOs and others making an effort to help preserve and protect the natural world.  The fund would start out with $10 billion and would begin issuing grants later in the year.

In November, the first Earth Fund award recipients were announced.  In total, 16 organizations will be receiving nearly $800 million in funding.

The largest awards include the following:  the Environmental Defense Fund received $100 million to build and launch MethaneSAT, a satellite that will locate and measure sources of methane pollution around the world and provide public access to data that assures accountability.

The Natural Resources Defense Council was awarded $100 million to advance climate solutions and legislation at the state level, promote policies and programs focused on reducing oil and gas production, protect and restore ecosystems that store carbon, and accelerate sustainable and regenerative agriculture practices.

The Nature Conservancy also received $100 million and plans to use the money to help protect the Emerald Edge forest.  (That is the largest intact coastal rainforest on Earth, spanning 100 million acres through Washington, British Columbia and Alaska).

The World Resources Institute will receive $100 million, doled out over five years, to be used to develop a satellite-based monitoring system to advance natural climate solutions around the world.

An additional $100 million award went to the World Wildlife Fund to help protect and restore mangroves, develop new markets for seaweed as an alternative to fossil fuel-based products, and to protect forests and other ecosystems around the world.

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The organizations that will benefit from Bezos’ $791M and what will they do with the money

Photo, posted March 4, 2015, courtesy of Kevin Gill via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Greenland Glaciers Past The Point Of No Return | Earth Wise

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Forty years of satellite data from Greenland shows that the glaciers on the island have shrunk so much that even if global warming came to an abrupt halt, the Greenland ice sheet would continue to shrink.

This conclusion was published in the journal Communications Earth and Environment by researchers at Ohio State University.  According to their study, Greenland’s glaciers have passed a tipping point where the snowfall that replenishes the ice sheet each year can no longer keep up with the ice that is flowing into the ocean from the glaciers.

The study analyzed monthly satellite data from more than 200 large glaciers that drain into the ocean around Greenland.  It looked at how much ice breaks off into icebergs or melts from the glaciers into the ocean as well as the amount of snowfall each year that replenishes the glaciers.

Throughout the 1980s and 90s, these two processes were mostly in balance, keeping the ice sheet intact.  But the amount of ice being lost each year started to increase steadily around the year 2000 while there was no increase in snowfall.   Both processes fluctuate from year to year, but the baseline for ice loss has steadily risen.  Before 2000, the Greenland ice sheet had about the same chance of gaining or losing mass each year.  At this point, the ice sheet is likely to gain mass in only one out of every 100 years.

Large glaciers in Greenland have retreated about 2 miles since 1985, so that many of them are sitting in deeper water with more ice in contact with warmer water making it harder for glaciers to grow back.  At this point, even if the climate reverses its trend, the ice sheet will continue to lose mass.

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Warming Greenland ice sheet passes point of no return

Photo, posted August 27, 2015, courtesy of Joxean Koret via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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