el nino

Climate Change And El Niño

December 2, 2019 By EarthWise Leave a Comment

The term El Niño refers to a large-scale ocean-atmosphere climate interaction linked to a periodic warming in sea surface temperature across the central and east-central equatorial Pacific Ocean. Amazingly, the phenomenon was originally recognized by fishermen off the coast of South America in the 1600s, with the appearance of unusually warm water in the Pacific Ocean.

According to a new study published in the Proceedings of the National Academy of Sciences, climate change is increasing the frequency of extreme El Niño events, leading to intensifying droughts, worsening floods, and shifting hurricane patterns.

The study, led by scientists in China and the US, looked at data from 33 El Niños dating back to 1901. Since the 1970s, El Niños have been forming farther to the west in the Pacific Ocean, where temperatures are warmer. Strong El Niños can cause severe drought in dry climates such as Australia and India, intense flooding in wetter climates such as the US Pacific Northwest and Peru, and more hurricanes to form in the Pacific and fewer in the Atlantic.

Before 1978, 12 out of 14 El Niños formed east of the International Dateline. Since 1978, all 11 have formed in the central or western Pacific Ocean a shift of hundreds of miles. There have been three so-called super El Niños since the shift – in 1982, 1997, and 2015. These have set new average temperature records and triggered catastrophic natural disasters.

With rising global temperatures, El Niños are likely to continue to intensify, with major impacts on human societies around the world.

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Climate Change is Making El Niños More Intense, Study Finds

Photo, posted January 20, 2016, courtesy of Los Angeles District via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change Is Not Natural

July 5, 2019 By EarthWise Leave a Comment

It has been the overwhelming consensus of the scientific community for a long time that human activity and other external factors are responsible for the continuing rise in global temperature. Despite this widespread agreement, there have been those who argue that natural ocean cycles might be influencing global warming over the course of multiple decades.

A new study, published in the Journal of Climate, provides an answer to the question of how much influence natural cycles might have, and that answer is very little to none.

The study looked at observed ocean and land temperature data since 1850 and, apart from human-induced factors such as greenhouse gas concentrations, took into account other occurrences such as volcanic eruptions, solar activity, and air pollution peaks. The findings demonstrated that slow-acting ocean cycles do not explain the long-term changes in global temperatures.

Based on the study, the researchers can state with confidence that human factors like greenhouse gas emissions and particulate pollution, along with year-to-year changes caused by natural phenomena like volcanic eruptions or El Niño, are sufficient to explain virtually all the long-term changes in temperature. The idea that the oceans could have been driving the climate either in a colder or warmer direction for multiple decades in the past and therefore will do so in the future is unlikely to be correct.

A number of previous studies have compared flawed observations with flawed modeling results to claim that naturally-occurring ocean cycles have played a large role in global temperatures. The new study shows that such cycles have little influence on the climate. Reducing greenhouse gas emissions is really what we need to do.

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Global temperature change attributable to external factors, confirms new study

Photo, posted November 13, 2007, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Bad News For Penguins

June 21, 2019 By EarthWise Leave a Comment

The second-largest breeding colony of emperor penguins in Antarctica, located in the Waddell Sea, has experienced “catastrophic breeding failure” for the past three years. Nearly all of the colony’s chicks have failed to survive due to the breakup of sea ice, according to a new study published in the journal Antarctic Science.

The colony was once home to 14,000 to 25,000 breeding pairs, which represents as much as 9% of the global emperor penguin population. Emperor penguins are the tallest and heaviest of all living penguins, reaching up to 4 feet in height and weighing between 50 and 100 pounds. They are the only penguin species that breeds during the Antarctic winter and their lengthy treks to breeding colonies have been the subject of numerous films and television shows.

Sea ice at Halley Bay in Antarctica had been stable and reliable for nearly 60 years but stormy weather in 2016 driven by El Nino conditions, strong winds, and record low ice extent caused the ice on which penguin chicks gather to break up. This happened again in 2017 and 2018. By last year, just a few hundred adult pairs were present at the breeding site and almost no chicks survived the ice breakup.

Researchers say that they have never seen a breeding failure on a scale like this in 60 years of studying the colonies. On a more positive note, while the population of the Halley Bay site has collapsed, the Dawson-Lambton breeding area – located about 34 miles away – has actually seen significant growth over the past four years. While this is encouraging, the growth at Dawson-Lambton does not fully compensate for the losses at Halley Bay, which was once considered relatively safe from the impacts of climate change.

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Emperor Penguin Colony Experiences “Catastrophic Breeding Failure”

Photo, posted February 22, 2011, courtesy of Krishna via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Forecasting A Bad Year For Carbon

March 11, 2019 By EarthWise Leave a Comment

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

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

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

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

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Faster CO₂ rise expected in 2019

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

Earth Wise is a production of WAMC Northeast Public Radio.

Indonesian Deforestation

February 28, 2019 By EarthWise Leave a Comment

Deforestation is defined as the intentional destruction of trees and other vegetation without reforesting or allowing the forest to regenerate itself.

In Indonesia, industrial agriculture, primarily for the production of palm oil, is a major driver of deforestation. But, according to researchers at Duke University, its impact has diminished proportionately in recent years as other natural and human causes have emerged. Their peer-reviewed findings were recently published in the journal Environmental Research Letters.

According to the study’s lead author, large-scale plantations were responsible for more than half of Indonesia’s deforestation in the late 2000s, peaking between 2008-2010 when an average of 1.5 million acres of forest was lost annually. The expansion of the massive plantations was responsible for 57% of the forest loss. Between 2014-2016, an average of more than 2 million acres of forest was lost annually, but plantation expansion only accounted for 25% of this figure. While the overall rate of deforestation continued to grow, other factors were responsible for most of it.

Conversions of forests to grasslands rose sharply in 2015 and 2016 when El Nino caused severe droughts and forest fires. Small-scale farming, often overshadowed by industrial agriculture, was also found to play a bigger role, accounting for 25% of all forest loss.

Indonesia has experienced some of the highest rates of deforestation. Its forests absorb and store vast amounts of climate-warming carbon dioxide, help prevent erosion and flooding, and provide habitat to thousands of species. Understanding the varied causes of Indonesian deforestation should help conservationists and policymakers better address the problem.

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Palm oil not the only driver of forest loss in Indonesia

Photo, posted March 26, 2018, courtesy of Achmad Rabin Taim via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saildrones For Science

July 11, 2018 By EarthWise Leave a Comment

Nine years ago, engineer Richard Jenkins broke the world land speed record for a wind-powered vehicle with a sailboat on wheels driving across a dry lakebed at 126 miles per hour. After years of engineering development, his technology has now taken on the form of a saildrone that can autonomously sail the sea gathering ecologic, oceanic and atmospheric data.

Losing Forests Is Felt Far Away

July 6, 2018 By EarthWise 2 Comments

Large areas of forests in our country are vulnerable to drought, fires and disease. When forests are heavily damaged, there are well-known local impacts: drier soils, stronger winds, increased erosion, loss of shade and loss of habitat.

Rising Seas On The East Coast

June 6, 2018 By EarthWise Leave a Comment

Global sea levels are rising by about a tenth of an inch per year, but in some places, the rise is faster… much faster. From 2011 to 2015, sea levels rose up to 5 inches – an inch per year – in some locales along the Eastern Seaboard. Places like Norfolk, Virginia and Miami are experiencing so-called sunny day flooding, something that had not been expected for decades according to climate projections. So, what is going on?

Indonesian Deforestation Continues

May 3, 2018 By EarthWise Leave a Comment

Worldwide, deforestation and land disturbance are responsible for about a quarter of all greenhouse gas emissions. The largest contributor to this problem is Indonesia and getting control of its emissions is a crucial part of meeting global carbon reduction targets.

2017 Was Hot

March 1, 2018 By EarthWise Leave a Comment

There’s no argument to be made about whether 2017 was hot or not. The only uncertainty is whether it was the second or third warmest year ever recorded.

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Winter Outlook

November 8, 2017 By EarthWise Leave a Comment

Each year around this time, the National Oceanic and Atmospheric Administration, or NOAA, releases its U.S. Winter Outlook that predicts overall weather trends around the country for the upcoming winter. They produce these seasonal outlooks to help communities prepare for the weather that is likely to be forthcoming.

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Solar Power And African Food Security

January 2, 2017 By EarthWise

Some of the poorest countries in the world are unfortunately among the most vulnerable to the effects of climate change. Malawi, for example, has 90% of its population in rural areas and 80% of its labor force is associated with agriculture.

The Hottest Month (Again)

September 15, 2016 By WAMC WEB

NASA data show that the Earth’s temperature in July was the highest recorded since record-keeping began 136 years ago. It was also the 10th straight month of record-breaking temperatures and was .18 degrees Fahrenheit higher than the previous hottest July in 2011.

Some Good News For Coral Reefs

August 12, 2016 By WAMC WEB

Most recent news about coral reefs around the world has been bad news. There has been unprecedented coral bleaching in places like Australia’s Great Barrier Reef. The effects of climate change – including warming temperatures and rising seas – as well as the recent El Niño event have led to damaged reefs across the globe.

Coral Bleaching On The Great Barrier Reef

May 9, 2016 By WAMC WEB

It was already well-known that coral bleaching was a serious problem in the Great Barrier Reef, but extensive aerial surveys and underwater dives have now revealed the shocking extent of the problem.

Bolivia’s Disappearing Lake

February 25, 2016 By WAMC WEB

Bolivia’s second largest lake has nearly disappeared. Lake Poopó, a saltwater lake located in a shallow depression in the Altiplano Mountains, used to cover an area about the size of Los Angeles. While it’s not the first time the lake has dried out, scientists believe its recovery hangs in the balance due to the combined stress of drought, climate change, and water diversion.

The Hottest Year

February 19, 2016 By WAMC WEB

2015 was the hottest year in the historical record, easily breaking the mark set only one year earlier. The unusually large El Niño weather pattern is releasing enormous amounts of heat from the Pacific Ocean into the atmosphere, but climate scientists say that the bulk of the record-setting heat is due to the long-term warming effects of greenhouse gas emissions. The global land surface temperature was 1.6°F above the 20th century historical average. That’s a huge jump from 2014, which was 1.3° above average. That may sound like very little, but for the planet as a whole, it is extremely large.

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Beware The Blob

February 1, 2016 By WAMC WEB

There has been plenty of discussion of El Niño, the periodic weather phenomenon in which prevailing easterly winds in the Pacific Ocean weaken, allowing warm water to move eastward and wreak havoc with the weather in North and South America. The current El Niño is a particularly strong one; some say it may be one of the strongest ever and are calling it the “Godzilla El Niño.”

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The Second Hottest Year On Record

January 29, 2016 By WAMC WEB

According to the National Oceanic and Atmospheric Administration – or NOAA – 2015 was the second hottest year ever recorded in the contiguous United States.

El Niño On The Way

September 8, 2015 By EarthWise

There are starting to be a lot of news reports about a strong El Niño being on the way later this year. El Niño is a weather phenomenon that occurs in the eastern tropical Pacific every two to seven years. East-to-west trade winds weaken and ocean surface temperatures go up. The result impacts the weather throughout the Pacific region.

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