americas

La Niña has arrived

February 26, 2025 By EarthWise Leave a Comment

After seven months of waiting following the end of the recent El Niño condition, La Niña finally showed up in the eastern Pacific Ocean in early December.

El Niño and La Niña are climate patterns in the Pacific Ocean that can affect weather worldwide. Normally, trade winds in the Pacific blow west along the equator, taking warm water from South America towards Asia. To replace the warm water, cold water rises from the depths. During El Niño, trade winds weaken and warm water is pushed back east, toward the west coast of the Americas. As a result, areas in the northern U.S. and Canada are dryer and warmer than usual.

During La Niña, trade winds are stronger than usual, pushing more warm water toward Asia. This results in more upwelling of cooler water from the depths. This tends to lead to drought in the southern U.S. and heavy rains and flooding in the Pacific Northwest and Canada. During a La Niña year, winter temperatures are warmer than normal in the South and cooler than normal in the North.

According to the report published in January by NOAA, the La Niña that has arrived is not a particularly strong one. Sea surface temperatures are only about 1.3 degrees Fahrenheit below average in the tropical Pacific. The report also suggests that the La Niña condition may not stick around very long.

The El Niño-Southern Oscillation phenomenon adds a natural source of year-to-year variability in global temperatures. The presence of La Niña for at least part of this year may temporarily keep the lid on rapidly climbing global temperatures.

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La Niña Is Here

Photo, posted November 23, 2011, courtesy of NASA Goddard Space Flight Center via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Who Can Solve The Plastic Waste Problem? | Earth Wise

June 21, 2022 By EarthWise Leave a Comment

Plastic packaging waste is a global problem. It collects in the oceans, breaks down into microplastics, which are consumed by fish and in turn by people who eat the fish. Only 14.5% of U.S. plastic waste is recycled. Most of it ends up in landfills, where is remains undegraded for hundreds of years.

A new international study explored the global patterns of plastic packaging waste. The study found that three countries – the U.S., Brazil, and China – are the top suppliers of waste. In terms of supply, the Americas generate 41% of the world’s production of plastic waste, Europe 24%, and Asia 21%.

That’s the plastics supply. As far as the consumers actually creating waste are concerned, the Americas represent 36% of the world’s packaging consumption, Asia 26%, and Europe 23%.

Packaging high-protein food such as meat, fish, and dairy is a major contributor to the waste problem. Plastic for this purpose is hard to replace and international exports exacerbate the problem, accounting for about 25% of plastic packaging waste.

International agreements typically focus on restrictions and fees on production. But that mostly creates strong incentives to simply relocate polluting activities to developing countries, which is a zero-sum game. There need to be incentives for consumers to reduce plastic use such as taxes on waste management, refunds on returning bottles, single-use plastic bans, and so on.

Who can solve the plastic waste problem? Everyone along the supply chain as well as the final consumers have to be part of the solution for reducing plastic waste.

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Producers and consumers must share burden of global plastic packaging waste

Photo, posted March 29, 2022, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

More Mega-Droughts | Earth Wise

December 2, 2020 By EarthWise Leave a Comment

According to a new report led by researchers from the University of Queensland in Australia, mega-droughts are expected to increase as global temperatures rise with the progression of climate change. While mega-droughts have no strict scientific definition, most studies – including this one – define them as prolonged droughts lasting two decades or longer.

The research team analyzed geological records from the Eemian Period – 129,000 to 116,000 years ago – to create a model of what to expect over the next 20-50 years. The Eemian Period is the most recent in Earth’s history when global temperatures were similar – or maybe even slightly warmer – than they are today.

By analyzing the climate during this period, the research team found that the world will likely experience increased water scarcity, reduced winter snow cover, more frequent wildfires and wind erosion as a result of global warming.

In the report, which was recently issued by the University of Queensland, the researchers collaborated with the New South Wales Parks and Wildlife Service to identify stalagmites in the northern section of Kosciuszko National Park. They were able to study small samples of calcium carbonate powder contained in the cave stalagmites, allowing them to identify periods of reduced precipitation during the Eemian Period.

Historically, mega-droughts have been associated with mass exoduses of people from the affected areas. In fact, mega-droughts are suspected of contributing to the collapse of several pre-industrial civilizations across Southeast Asia and the Americas.

If humans continue to warm the planet, the researchers say more mega-droughts will be in our future.

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Expect more mega-droughts

Photo, posted March 28, 2014, courtesy of Marufish via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Pandemic Lockdowns And Carbon Emissions | Earth Wise

November 25, 2020 By EarthWise Leave a Comment

The early months of the COVID-19 pandemic saw many human activities reduced to a fraction of what they were previously. Notably, air pollution in major cities was dramatically lower than it had been in decades. Now, a new study has looked at the effect of the pandemic shutdowns on carbon dioxide emissions.

An international team of climate scientists has published an assessment of carbon dioxide emissions by industry, transportation, and other sectors from January through June. According to their measurements, this year’s pandemic lockdowns resulted in a 9% decline in emissions from 2019 levels.

An earlier study reported a 17% drop in CO2 emissions, but the new study was more comprehensive and detailed.

The new data includes estimates of day-by-day, sector-specific and country-level differences in CO2 emissions derived from frequently updated data sources, some of which are nearly in real-time. It tracks the effects of COVID-19-related disruptions of human activities in China starting in February and in the United States and Europe in March through May.

The data revealed the resumption of emissions in many regions, such as in China, where they are now back to pre-pandemic levels. Emissions in the Americas and Europe have been slower to recover, especially in the US, where COVID-19 hotspots are continuing to emerge.

The reduction in carbon emissions has been due mostly to transportation with fewer people driving to work and traveling by air. Even by June, when lockdowns were easing, global emissions were still significantly reduced. In any case, a pandemic is a highly undesirable and unwelcome way to reduce carbon emissions, but the data from this year does show that it is effective.

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Pandemic lockdowns caused steep and lasting carbon dioxide decline

Photo, posted August 7, 2020, courtesy of Michael Mueller via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Shrinking Ice In The Bering Sea | Earth Wise

October 19, 2020 By EarthWise Leave a Comment

The Bering Sea forms the divide between the two largest landmasses on Earth: Eurasia and the Americas. Recent analysis of vegetation from a Bering Sea island has determined that the extent of sea ice in the region is the lowest it has been for over 5,000 years.

St. Matthew Island, a small island in the middle of the Bering Sea, has essentially been recording what is happening in the ocean and atmosphere around it, in the form of the composition of peat layers on the island. By analyzing the chemical composition of peat core samples, scientists can estimate how sea ice in the region has changed over the course of time.

Changes in the relative amounts of two oxygen isotopes in the sediment and plant debris trapped in the peat on the island reflect the nature of precipitation during the period when the peat layers formed. That ratio is correlated with the amount of sea ice in the region. Satellite data acquired over the past 40 years confirms this correlation.

Analysis of the data shows that the current ice levels are unprecedented in the last 5,500 years. These long-term findings affirm that reductions in Bering Sea ice are due to more than recent higher temperatures associated with global warming. Atmospheric and ocean currents, which have also been altered by climate change, play a large role in the presence of sea ice.

Summertime sea ice in the Arctic was expected to reach its second-lowest extent in September in 40 years of observation. Sea ice typically builds up again each winter, but the changes in ice extents actually lag behind changes in greenhouse gas level by decades. Future ice loss is already built into the system.

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Bering Sea ice extent is at most reduced state in last 5,500 years

Photo, posted December 2, 2012, courtesy of Bering Land Bridge National Preserve via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Crocodiles And Climate Change

January 25, 2016 By WAMC WEB

Crocodiles are large aquatic reptiles that live throughout the tropics in Asia, Africa, the Americas, and Australia. The first crocodiles appeared approximately 240 million years ago – around the same time as dinosaurs. And while the resilient species did survive the last great extinction, crocodiles might not be climate change-proof after all.