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Why Was the Summer So Hot? | Earth Wise

September 4, 2023 By EarthWise Leave a Comment

Many places around the world have experienced extraordinary heat waves this summer. The 31 days of high temperatures 110 degrees or more in Phoenix is a prime example but many other places suffered from extreme and relentless heat. Why did this happen?

The overarching reason is climate change, which has warmed the Earth by 2.2 degrees Fahrenheit since the preindustrial era. This change on a global level is enough to make heatwaves far more likely. For example, the concurrent heatwaves in Europe and North America were 1000 times more likely to have occurred because of climate change.

But there hasn’t been a sudden increase in global temperature that would make this summer so much hotter. Instead, what really has happened is three other factors all came into play at the same time.

The first is the 2022 eruption of Hunga Tonga-Hunga Ha-apai, which is an underwater volcano in the South Pacific. That eruption did not produce much in the way of planet-cooling aerosols in the atmosphere. Instead, it vaporized huge amounts of seawater, sending water vapor into the atmosphere, which helps trap heat.

The second is a change in the amount of energy radiating from the sun. That actually rises and falls a small amount every 11 years. Currently, it is in the upswing and will reach its next peak in 2025.

Finally, there is the arrival of the El Niño in the Pacific, whose balmy ocean waters radiate heat into the air.

The combination of all these factors when added to the already warming climate is a recipe for temperatures to soar to uncharted highs. We can expect more heat waves, forest fires, flash floods, and other sorts of extreme weather.

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It’s Not Just Climate Change: Three Other Factors Driving This Summer’s Extreme Heat

Photo, posted February 27, 2017, courtesy of Giuseppe Milo via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

El Niño Will Likely Return | Earth Wise

June 21, 2023 By EarthWise Leave a Comment

El Niño, a weather phenomenon triggered by warm waters in the eastern Pacific, is likely to return this year, according to the World Meteorological Organization. The Pacific has been in the cooler La Niña phase for the past 3 years, which is unusual, but that appears to be coming to a close. According to the WMO, there is an 80% chance that the Pacific will shift to the El Niño phase before fall.

Record hot years typically coincide with El Niño, which adds to the ongoing warming trend in the climate. There is not yet a clear picture of how strong the forthcoming El Niño event will be or how long it might last, but even a mild El Niño could affect precipitation and temperature patterns around the world.

The hottest year on record, 2016, occurred during a particularly strong El Niño. Experts expect that 2024 is likely to see soaring temperatures again. El Niño generally leads to drier conditions in Australia, Indonesia, and southern Asia, but greater amounts of rainfall in South America, the U.S., and parts of Africa. Despite the presence of a cooling La Niña for the past three years, the last eight years have been the hottest on record.

El Niño and La Niña form an intermittent cycle known as the El Niño Southern Oscillation, or ENSO, that is highly influential in shaping the year-to-year variations in weather conditions around the world. ENSO is a natural phenomenon and scientists are still trying to understand how human-caused climate change might be impacting the behavior and dynamics of the cycle.

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‘A New Spike’ in Global Temperatures in the Forecast

Photo, posted October 11, 2015, courtesy of Harshil Shah via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

2022 Temperature Report | Earth Wise

February 8, 2023 By EarthWise Leave a Comment

The average surface temperature for the Earth in 2022 tied with 2015 as the fifth warmest on record. The warming trend for the planet continued with global temperatures 1.6 degrees Fahrenheit above the average baseline for 1951-1980 that NASA uses for its studies. Compared with the late 19th century average used in setting climate goals, global temperatures are up about 1.1 degrees Celsius, or 2 degrees Fahrenheit.

Overall, the past nine years have been the warmest since modern recordkeeping began in 1880. The rising temperatures have moved in concert with rising levels of greenhouse gases entering the atmosphere from human activity. Many factors can affect the average temperature in any given year including El Nino and La Nina conditions in the Pacific. But the longer-term trend is quite clear. Global temperatures continue to rise.

Greenhouse gas emissions have reached all-time high levels despite increasing efforts to reduce them. There was a real drop in levels in 2020 due to reduced activity during COVID-19 lockdowns, but they rebounded soon thereafter.

The Arctic region continues to experience the strongest warming trends, as much as four times the global average. Arctic warming has a major impact on weather at lower latitudes as it changes the behavior of the jet stream as well as affecting ocean currents and water temperatures.

As global temperatures continue to rise, rainfall and tropical storms have become more intense, droughts have become more severe, and ocean storm surges have had increasing impact. From torrential monsoons in Asia to megadroughts in the U.S. Southwest, extreme weather has become the new normal.

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NASA Says 2022 Fifth Warmest Year on Record, Warming Trend Continues

Photo, posted June 20, 2020, courtesy of Daxis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Some Good News For The Great Barrier Reef | Earth Wise

September 5, 2022 By EarthWise Leave a Comment

It seems like there has been nothing but dire news from Australia’s Great Barrier Reef. Earlier this year, there was yet another mass bleaching event – the fourth in seven years and the first ever to strike during a cooler La Niña phase in the Pacific. But this bleaching event was less severe than other recent ones, which makes it possible for parts of the reef to bounce back.

In particular, in the northern and central stretches of the reef, scientists have recorded the most extensive coral cover seen in 36 years of study. In areas where coral cover has expanded, it is mostly fast-growing Acropora corals driving the growth. That isn’t the best outcome, given that Acropora are particularly vulnerable to strong waves, highly susceptible to bleaching, and are the preferred target of crown-of-thorns starfish.

Those creatures are a major problem for the Great Barrier Reef. In contrast to the upper stretches of the reef, the southern third actually saw coral cover drop from 38 to 34 percent over the course of the past year. Scientists blame the decline on an outbreak of crown-of-thorns starfish, which prey on corals. The starfish grow faster and eat more in warmer, more acidic waters. Carbon emissions are both raising ocean temperatures and turning waters more acidic.

The large increases in hard coral cover in the reef are certainly good news, but it is important to understand that they can be quickly negated by disturbance on reefs where Acropora corals predominate. Warming temperatures and mass bleaching events continue to pose a critical threat to all reefs, especially when there are crown-of-thorns starfish outbreaks and increasing frequency of tropical cyclones.

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Parts of Great Barrier Reef See Most Extensive Coral Cover In 36 Years

Photo, posted July 15, 2019, courtesy of Kenneth Lu via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Marine Predation And Climate Change | Earth Wise

July 11, 2022 By EarthWise Leave a Comment

Climate change is taking a toll on forests, farms, freshwater resources, and economies all around the world. But ocean ecosystems remain the center of global warming.

Despite their vast ability to absorb heat and carbon dioxide, oceans are warming. In fact, according to scientists, the oceans have absorbed 90% of all the warming that has occurred during the past 50 years.

The ocean’s surface layer, which is home to most marine life, takes most of this heat. As a result, the top 2,300 feet of global ocean water has warmed approximately 1.5°F since 1901.

Well it turns out that a hotter ocean is also a hungrier ocean. According to a new study recently published in the journal Science, researchers discovered that predator impacts in the Atlantic and Pacific oceans peak at higher temperatures. The effects of more intense marine predation could disrupt ecosystem balances that have existed for millennia.

An international research team led by the Smithsonian Institution and Temple University analyzed predator and prey data collected from 36 sites, running along the Atlantic and Pacific coasts from Alaska in the north to Tierra de Fuego at the tip of South America. The research team found that, in warmer waters, predators’ more voracious appetites left outsized marks on the prey community. Total prey biomass plunged in warmer waters when prey were left unprotected. However, in the coldest zones, leaving prey exposed or protected made nearly no difference at all.

As the oceans continue to warm, more intense predation will create winners and losers and could jeopardize the overall health of marine ecosystems.

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As the ocean heats up hungrier predators take control

Photo, posted July 14, 2017, courtesy of Jonathan Chen via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Alaskan Icemageddon | Earth Wise

January 25, 2022 By EarthWise 1 Comment

December saw some wild weather in Alaska. A combination of record high temperatures and torrential rainstorms resulted in the coining of the term “Icemageddon” to describe what was going on with the weather.

Kodiak Island in southern Alaska saw a high temperature of 67 degrees on December 26, which was warmer than it was in Southern California that same day. This set an all-time record for the warmest December day in Alaska. Such a high temperature is amazing considering how little sunlight Alaska gets at this time of year. And with warmer air comes wetter air, as the atmosphere is capable of holding more water vapor as temperatures increase.

As a result, that same day saw the interior of the state get an inch of rain in just a few hours, something that hadn’t happened for decades. But then, when temperatures plummeted again, all that rainwater froze.

Huge sheets of ice blocked roads and choked traffic in Fairbanks, Alaska’s second largest city. Indeed, it was the state’s transportation department that came up with the term icemageddon to describe the situation.

The extreme warmth in December is related to the same weather pattern that brought cold, wintry weather to the Pacific Northwest and Northern California. Those weather conditions resulted in hundreds of cancelled flights in Seattle, where temperatures dropped into the 20s, and in massive amounts of snowfall in the Sierra Nevada mountains in California. A strong area of high pressure anchored in the Northern Pacific resulted in a clockwise flow around it drawing warmer, more tropical air from the Pacific up to Alaska.

Climate change continues to push the envelope on what sort of weather is possible all over the world.

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Alaska faces ‘Icemageddon’ as temperatures swing wildly

Photo, posted April 30, 2015, courtesy of Naql via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Coral Reef Status Report | Earth Wise

December 23, 2021 By EarthWise Leave a Comment

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.

Coral Reefs And Fish Survival | Earth Wise

August 25, 2021 By EarthWise Leave a Comment

The precarious state of the world’s coral reefs has been a highly visible subject for a decade or more. Mostly what we hear about is the loss of some of the most beautiful sights on the planet. But there is far more at stake than scenic wonders.

The warming and acidifying of ocean waters are causing corals to increasingly bleach and often die. Corals provide a unique food source for some species of fish and a three-dimensional habitat for many others. The fish that depend on corals are often prey for fish that don’t depend directly on corals and so on up the food chain.

What happens to fish when coral reefs disappear? The fish species that feed on corals will starve while others will seek alternative rocky habitats.

A new study by the University of Helsinki uses statistical methods to predict how fish diversity will respond to declines in coral diversity. It concludes that a future coral loss might cause a 40% reduction in reef fish diversity globally. This is more than a loss of colorful sights for snorkelers; reef fishes provide essential protein for millions of people around the world.

The estimate of potential loss of fish species greatly exceeds the number of species known to depend directly or even indirectly on coral. The implication is that coral reef food webs will begin to unravel if corals go extinct. This unraveling is expected to be worse in some places than others. The Central Pacific, for example, could lose 60% of its reef fish.

For both snorkelers and for the millions who depend upon reef fishes for food, the need for greater efforts to conserve and restore coral reefs is apparent.

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A future ocean that is too warm for corals might have half as many fish species

Photo, posted September 27, 2009, courtesy of Matt Kieffer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

California Offshore Wind | Earth Wise

June 28, 2021 By EarthWise Leave a Comment

Offshore wind has been pretty much a non-starter in the U.S. until recently. Now there is considerable activity in the Northeast Atlantic with major projects getting started off the coasts of Massachusetts, New York, and other eastern states. The prospects for wind farms in the Pacific, on the other hand, have been pretty dismal. There are significant logistical problems posed by a deep ocean floor and also opposition from the Navy that does not want obstacles for its ships.

A combination of progress in floating wind turbine technology and the arrival of an administration highly supportive of renewable energy technology has changed the situation. In late May, the Navy abandoned its opposition to Pacific offshore wind and joined the Interior Department in giving support to allowing two areas off the California coast to be developed for wind turbines.

The plan allows commercial offshore wind farms in a 400-square-mile area in Morro Bay in central California, and in another area off the Humboldt Coast in Northern California.

The two California sites could support enough wind turbines to generate electricity to power 1.6 million homes. That would make the California coast one of the largest generators of wind power in the world. The forthcoming Vineyard Wind farm in Massachusetts is expected to have 84 giant turbines. The two California sites could hold more than 300 turbines.

The offshore wind industry is booming around the world, especially near the coasts of Norway and the UK, where the water is shallow, and turbines can be anchored to the ocean floor. By contrast, the Pacific Ocean floor drops steeply from the coastline, making it too deep to anchor wind towers. The newly emerging technology of floating turbines is the key to establishing offshore wind in the Pacific.

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Biden Opens California’s Coast to Wind Farms

Photo, posted August 7, 2013, courtesy of Ray Bouknight via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Sharks On The Decline | Earth Wise

September 4, 2020 By EarthWise Leave a Comment

During the past 70 years, global shark populations have been on the decline. Many species have become threatened or endangered. Conservation efforts have been underway in many places, but shark populations continue to be at risk because of over-fishing and habitat loss.

A comprehensive study by marine biologists at Texas A&M University deployed more than 15,000 baited remote underwater video stations on 371 coral reefs in 58 countries. The study included 59 different shark species in the Atlantic, Pacific and Indian Oceans. The researchers were surprised to find that no sharks at all were detected in almost 20% of the locations surveyed and were almost completely absent from coral reefs in several nations.

Scientists believe that demand for shark products, such as fins and meat, and bycatch (that is, sharks captured in nets by fisherman trapping other kinds of fish) are strong contributors to the widespread declines in shark numbers around the world.

The study shows that if corrective steps are not taken in regions where marine management is still ineffective, continued depletion of shark populations is highly likely.

Sharks have important roles in marine ecosystems. When their habitats deteriorate and their populations decrease, ecosystem stability and health is degraded because sharks help regulate prey populations.

Some countries, notably the Bahamas, are combating the problem by providing sanctuaries for sharks where fishing and harvesting is prohibited. Such places support some of the healthiest shark populations in the world. However, the decline of coral reefs is just another challenge facing shark populations around the world.

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Study Shows Alarming Decline In Shark Numbers Around The World

Photo, posted January 9, 2017, courtesy of Kris-Mikael Krister via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Why The Arctic Is Warming So Fast | Earth Wise

April 7, 2020 By EarthWise Leave a Comment

The Arctic has been warming at the fastest rate of any place on Earth. There have long been observations of amplification of Arctic warming, meaning that its temperature increases have been well above what would be expected from the global temperature rise.

Many climate models have attributed this warming to the melting of sea ice. As the bright white ice disappears for longer periods of the year, the dark surface waters that are exposed absorb sunlight rather than reflecting it back into space the way the ice does. This is known as the ice-albedo feedback. But it does not entirely explain the amount of warming in the Arctic.

Researchers at the Scripps Institution of Oceanography have developed a new theory that helps to explain what is going on.

In the areas of the Arctic Ocean where there is sea ice, the water is actually warmer at depth and colder near the surface. The deeper waters are fed by the relatively warm Pacific and Atlantic Oceans while the surface water is cooled by the ice. The increasing temperature difference between surface and deeper water causes a greater upward flow of heat. This was first observed in research cruises that revealed evidence that the Arctic Ocean water was becoming more turbulent over time.

According to computer modeling, this phenomenon is responsible for about 20% of the amplification of global warming that occurs in the Arctic.

There are multiple ongoing studies looking at the Arctic warming trend. Other factors that have contributed over time are the presence of chlorfluorocarbons in the atmosphere. That contribution is waning since the use of CFCs has been phasing out over time.

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Researchers Find New Reason Why Arctic is Warming So Fast

Photo, posted April 19, 2017, courtesy of Markus Trienke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fish And Ships

April 25, 2019 By EarthWise Leave a Comment

Solutions to overfishing of certain tuna and shark populations have been hindered by some significant unknowns: where the fishing is happening, and where the fish are. But researchers from Stanford University have recently shed some light on this mystery.

According to a paper recently published in the journal Science Advances, the researchers have developed a map of shark, tuna, and ship movements that could help ocean managers identify regions of the sea where vulnerable species may be at risk.

The researchers’ work builds on a 2018 study in which four years of satellite vessel movement data was used to develop a machine learning algorithm that mapped the footprint of 70,000 different fishing vessels around the world. In their paper, the researchers zeroed in on the activities of 900 vessels from 12 countries in the northeast Pacific Ocean to figure out to what degree fishing fleets, sharks, and tunas overlapped.

The researchers combined the vessel data with the ocean habitat preferences of sharks and tunas obtained from a decade-long tracking program called Tagging of Pacific Predators (or TOPP). According to the IUCN, most of the 876 individuals tagged in TOPP belong to species that are either threatened or near-threatened.

By synthesizing this data, researchers were able to map where sharks and tunas would have the highest overlap with commercial fishing vessels. Increasing the transparency of where fish meets fleets will allow ocean managers to determine where international protections may be needed.

The United Nations is currently developing the world’s first legally binding treaty to protect international waters. The Stanford University researchers hope their findings can help with this treaty’s formulation.

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