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Carbon Dioxide Levels Higher Again | Earth Wise

July 5, 2022 By EarthWise Leave a Comment

The National Oceanic and Atmospheric Administration reported that carbon dioxide levels measured in May at the Mauna Loa Observatory reached a value of 421 parts per million. This is 50% greater than pre-industrial levels and is in a range not seen on earth for millions of years.

Before the Industrial Revolution, CO2 levels fairly steadily measured around 280 parts per million, pretty much for all 6,000 years of human civilization. Since the Industrial Revolution began in the 18th century, humans have generated an estimated 1.5 trillion tons of CO2 pollution, much of which will continue to warm the atmosphere for thousands of years.

The present levels of carbon dioxide are comparable to those of an era known as the Pliocene Climatic Optimum, which took place over 4 million years ago.

The bulk of the human-generated carbon dioxide comes from burning fossil fuels for transportation and electrical generation, from cement and steel manufacturing, and from the depletion of natural carbon sinks caused by deforestation, agriculture, and other human impacts on the natural environment.

Humans are altering the climate in ways that are dramatically affecting the economy, infrastructure, and ecosystems across the planet. By trapping heat that would otherwise escape into space, greenhouse gases are causing the atmosphere to warm steadily, leading to increasingly erratic weather episodes ranging from extreme heat, droughts, and wildfires, to heavier precipitation, flooding, and tropical storm activity.

The relentless increase of carbon dioxide measured at Mauna Loa is a sober reminder that we need to take serious steps to try to mitigate the effects of climate change.

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Carbon dioxide now more than 50% higher than pre-industrial levels

Photo, posted December 20, 2016, courtesy of Kevin Casey Fleming via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Record Levels Of Deforestation In The Amazon | Earth Wise

March 25, 2022 By EarthWise Leave a Comment

The Amazon rainforest is the largest rainforest in the world, covering more than 2.5 million square miles. It’s home to 10% of all known species in the world. The Amazon rainforest’s biodiversity is so rich that scientists are still discovering new plant and animal species today.

The Amazon rainforest absorbs huge amounts of carbon dioxide from Earth’s atmosphere, making it a key part of mitigating climate change. The vast rainforest acts as what’s known as a carbon sink. Simply put, a carbon sink is anything that absorbs more carbon from the atmosphere than it releases. But as trees in the Amazon disappear, so does the ability of the rainforest to absorb carbon dioxide.

Deforestation of the Amazon rainforest remains a major problem. According to satellite data from the Brazilian government, the number of trees cut down in the Brazilian Amazon in January far exceeded deforestation figures for the same month last year. Approximately 166 square miles of land was deforested in January alone, which is five times greater than what was lost in January, 2021.

Cattle ranching – both for beef and for leather – remains the leading cause of deforestation in the Amazon rainforest. Trees in the Amazon are also cut down for their wood, as well as to clear the land in order to grow food crops, such as soy, sugar, and oil palm.

Many companies have pledged to achieve “net zero” deforestation in their supply chains over the years, but most have not lived up to the commitment.

Deforestation is not only a major driver of climate change, but it’s also the leading cause of species extinction. Preserving the Amazon rainforest is vital.

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Amazon deforestation: Record high destruction of trees in January

Greenpeace calls on fast food giants to take a stand against Bolsonaro’s Amazon destruction

Hundreds of Companies Promised to Help Save Forests. Did They?

Photo, posted July 14, 2018, courtesy of Alexander Gerst via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Mercury In The Amazon Rainforest | Earth Wise

March 8, 2022 By EarthWise Leave a Comment

Recent research has found that some of the highest levels of mercury pollution ever recorded are in a patch of pristine Amazonian rainforest. The international team of researchers discovered that illegal goldmining in the Peruvian Amazon is the source of the pollution.

Illegal miners separate gold particles from river sediments using mercury. Mercury binds to gold, forming pellets large enough to be caught in a sieve. The pellets are then burned in open fire ovens, releasing the mercury to the atmosphere, leaving the gold behind. The mercury smoke ends up being washed into the soil by rainfall, deposited onto the surface of leaves, or directly absorbed into leaf tissues.

Deforested areas had low levels of mercury, while the areas with the largest, densest old-growth trees captured huge volumes of atmospheric mercury, more than any other ecosystem studied in the entire world. Mercury levels were directly related to leaf area index: the denser the canopy, the more mercury it holds. Birds from this area have up to twelve times more mercury in their systems than birds from less polluted areas. Such high concentrations of mercury could provoke a decline of up to 30% in these birds’ reproductive success.

Small-scale artisanal gold mining is an important livelihood for local communities. Eliminating it outright may not be a viable solution but coming up with ways to continue to provide a sustainable livelihood while protecting communities from poisonous pollution is essential.

In the meantime, the forests are doing an important service by capturing much of the mercury and preventing it from getting into the general atmosphere and endangering more people and animals. Burning or harvesting the mercury-ridden trees would release the mercury back into the atmosphere.

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Modern Day Gold Rush Turns Pristine Rainforests into Heavily Polluted Mercury Sinks

Photo, posted August 24, 2016, courtesy of Anna and Michal via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Pandemic And Global Temperatures | Earth Wise

March 12, 2021 By EarthWise Leave a Comment

The early months of the Covid-19 pandemic last year saw dramatic reductions in travel and many forms of commerce. With much of human activity greatly curtailed, greenhouse gas emissions were greatly reduced. And yet, all of that did not slow down global warming: 2020 ended up tied with 2016 as the warmest year on record and atmospheric greenhouse gas levels reached a new high.

In order to understand how this came about, it is necessary to understand the complex climate influences of different types of emissions from power plants, motor vehicles, industrial facilities, and other sources. The fact is that some types of pollution actually have a cooling effect rather than contributing to global warming.

Tiny industrial pollution particles called aerosols actually make clouds brighter, causing them to reflect away more solar heat from the surface of the planet. During the drastic shutdown last year, the biggest emissions decline was from the most polluting industries. The reduction of aerosols had immediate, short-term effects on temperatures. These types of pollutants are very bad for human health, but when they are present, they do have the effect of reducing temperatures.

It is important to keep in mind that carbon dioxide spreads through the Earth’s atmosphere and stays there for a century or more, trapping heat on a global scale. Industrial aerosols stay relatively concentrated in the region where they are emitted and are often removed by rain and winds within a few weeks. So, their cooling effect doesn’t spread very far or last very long.

Overall, the initial pandemic slowdown probably didn’t have any real long-term impact on the climate but over the short term, the effects were not as simple as one might expect.

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Covid-19 Cut Gases That Warm the Globe But a Drop in Other Pollution Boosted Regional Temperatures

Photo, posted July 7, 2020, courtesy of Joey Zanotti via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Benefits Of A Zero-Emissions Boston | Earth Wise

May 25, 2020 By EarthWise Leave a Comment

Many countries, states, and cities around the world have set goals to become carbon neutral, typically by the year 2050. These goals are based on the desire to mitigate the effects of climate change that are steadily increasing as a result of the buildup of carbon dioxide in the atmosphere. But reducing emissions is not just a way to combat climate change, it can also be a major contributor to improved public health.

The City of Boston has set a goal to become carbon neutral by 2050. A new study by the School of Public Health at Boston University published in the journal Environmental Research Letters looked at the consequences of eliminating fossil fuel emissions in the greater Boston area.

According to their modeling, eliminating emissions would save 288 lives a year by reducing fatal and non-fatal cardiovascular and respiratory illnesses. The resulting decrease in medical costs and lost and reduced work could save $1.7 billion a year in Suffolk County and $2.4 billion a year for the entire 75-square-mile zone modeled in the study.

The study looked at the amounts of two air pollutants known to harm human health: PM2.5 (particulates with a diameter of less than 2.5 microns) and ozone. They compared the current levels of these pollutants to what would be present when contributions from motor vehicles, generators, rail, industry, oil- and gas-burning, shipping and boating, and residential wood fires were eliminated.

The study focused on the City of Boston’s climate action plan, but actions taken by Boston will not take place in a vacuum. Many cities across the region are taking similar actions. The overall results will come from the collective actions across New England.

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A Zero-Emissions Boston Could Save 288 Lives and $2.4 Billion Annually

Photo, posted August 31, 2019, courtesy of Eric Kilby via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Reducing Air Pollution With Plants | Earth Wise

January 15, 2020 By EarthWise Leave a Comment

New research by Ohio State University suggests that adding plants and trees to the landscapes near factories and other pollution sources could reduce air pollution by an average of 27%. In addition, the study indicates that, in many cases, plants may be a cheaper option for cleaning the air than more technological approaches.

The study looked at public data on air pollution and vegetation on a county-by-county basis across the lower 48 states. It then calculated what adding additional trees and plants might cost. The calculations included the capacity of current vegetation to mitigate air pollution as well as the effects that restorative planting might have on pollution levels.

In 75% of the counties analyzed, it was cheaper to use plants to mitigate air pollution rather than add technological interventions such as smokestack scrubbers to the sources of pollution. The results varied according to the pollution source. For example, technology is cheaper at cleaning the air near industrial boilers than ecosystem approaches. For the broad manufacturing industry, one approach or the other was favorable, depending on the type of factory.

Adding trees or other plants generally can lower air pollution levels in both urban and rural areas, although success rates depend on a variety of factors including how much land is available to grow new plants and current air quality.

Reducing air pollution is critical to public health. An estimated 4 in 10 people in the U.S. live in areas with poor air quality, leading to health issues including asthma, lung cancer, and heart disease. The study shows that nature should be part of the planning process for industry to deal with air pollution.

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Nature might be better than tech at reducing air pollution

Photo courtesy of 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.

Another CO2 Milestone

May 22, 2018 By EarthWise Leave a Comment

The global concentration of carbon dioxide in the atmosphere was measured at 400 parts per million for the first time in recorded history in May of 2013. It was a brief event at the Mauna Loa Observatory in Hawaii at the time. Within the next couple of years, however, readings of at least 400 ppm became standard.