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Greenhouse Gases Continue To Rise | Earth Wise

May 24, 2023 By EarthWise Leave a Comment

Despite all the focus on reducing emissions of greenhouse gases, there continues to be little progress toward actually accomplishing reductions. A combination of growing populations, increasing industrialization in the developing world, and just plain reluctance on the part of many sectors of society to act, have all contributed to the continuing buildup of climate-altering gases in the atmosphere.

Levels of carbon dioxide, methane, and nitrous oxide – the three greenhouse gases produced by human activity that are the major contributors to climate change – all continued historically high rates of growth in 2022.

CO2 levels rose by 2.13 parts per million last year, roughly the same rate observed during the past decade. The current level of 417 ppm is 50% higher than pre-industrial levels. Increases of more than 2 ppm have occurred for 11 consecutive years. Prior to 2013, there had never even been 3 years in row with increases of that size.

Methane levels increased by 14 parts per billion, the fourth largest increase over the past 40 years. Methane levels in the atmosphere are now two-and-a-half times greater than their pre-industrial level.

The third most significant greenhouse gas – nitrous oxide – also saw a large increase, reaching 24% above pre-industrial levels.

Carbon dioxide emissions are by far the most important contributor to climate change and the continuing widespread burning of fossil fuels is the primary source. There are widespread intentions to reduce carbon dioxide emissions, but those intentions have not yet resulted in sufficient actions.

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Greenhouse gases continued to increase rapidly in 2022

Photo, posted May 16, 2014, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Mangrove Forests And Climate Change | Earth Wise

August 3, 2022 By EarthWise Leave a Comment

Mangrove forests play a vital role in the health of our planet. These coastal forests are the second most carbon rich ecosystems in the world. A patch of mangrove forest the size of a soccer field can store more than 1,000 tons of carbon. It does this by capturing carbon from the air and storing it in leaves, branches, trunks, and roots.

Mangrove forests only grow at tropical and subtropical latitudes near the equator because they cannot withstand freezing temperatures. These forests can be recognized by their dense tangle of prop roots that make the trees look like they are standing on stilts above the water. These roots allow the trees to handle the daily rise and fall of tides. Most mangroves get flooded at least twice a day. The roots also slow the movement of tidal waters, which allows sediments to settle out of the water and build up on the muddy bottom. Mangrove forests stabilize coastlines, reducing erosion from storms, currents, waves, and tides.

A new study by the University of Portsmouth in the UK looked at the effects of climate change on how carbon is stored in mangrove forests. In mangrove ecosystems, a variety of organisms break down fallen wood. These include fungi, beetle larvae, and termites. Closer to the ocean, clams known as shipworms degrade organic material.

Climate change is disrupting these processes in at least two ways. Rising sea levels are changing the way sediments build up and increased ocean acidity is dissolving the shells of marine organisms like shipworms.

Mangrove forests are crucial to mitigating climate change, and changes to the functioning of the carbon cycle of those ecosystems are a threat to their ability to perform that function.

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Study Reveals How Climate Change Can Significantly Impact Carbon-Rich Ecosystem

Photo, posted March 24, 2014, courtesy of Daniel Hartwig via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Weather Disasters On The Rise | Earth Wise

November 1, 2021 By EarthWise Leave a Comment

It seems like the news is always filled with stories about storms, heatwaves, drought, and forest fires. This is because these things are happening with unprecedented frequency.

According to a new report from the World Meteorological Organization, weather disasters have become five times more common since 1970, in large part a result of climate change. Extreme weather, climate, and water events are increasing and are becoming more frequent and severe in many parts of the world.

Between 1970 and 2019, there were more than 11,000 reported disasters attributed to weather, resulting in over 2 million deaths and $3.64 trillion dollars in economic losses.

Storms and floods were the most prevalent disasters. The five costliest disasters ever are all hurricanes that have struck the United States over the past 20 years.

Droughts accounted for the greatest number of human losses, with severe droughts in Ethiopia, Mozambique, and Sudan responsible for 650,000 deaths.

About the only positive news in the report was that even as disasters have grown more prevalent, deaths have declined, dropping from about 50,000 a year in the 1970s to fewer than 20,000 in the 2010s. This is a result of better early warning systems. We have gotten better at saving lives. But early warning systems are woefully insufficient in much of the developing world, where more than 90% of disaster-related deaths occur.

Of the 77 weather-related disasters that struck between 2015 and 2017, 62 show the influence of human-caused climate change. With the pace of climate change now accelerating, there are likely to be more frequent catastrophic disasters in the years to come.

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As the Planet Has Warmed, Weather Disasters Have Grown Fivefold, Analysis Shows

Photo, posted September 16, 2021, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Keeping Charleston Dry | Earth Wise

June 11, 2020 By EarthWise Leave a Comment

Charleston, South Carolina is visited by millions of tourists each year. The town is a glimpse into the past, showcasing antebellum mansions, row houses, historic African American churches and scenic harbor views from a Civil War-era promenade.

Charleston is also visited more and more by water from rising seas and increasingly powerful storms. The city is essentially drowning in slow motion and may soon face an existential threat to its survival.

Charleston has a harbor and three rivers and water from all these sources leaks in at every bend and curve, fills streets, disrupts businesses, and rushes into homes during storms. Million-dollar antebellum mansions, built on spongy marsh and old tidal creeks, flood repeatedly.

City officials have endorsed a plan by the U.S. Army Corps of Engineers to wall off the historic downtown with an 8-mile-long seawall that would cost nearly $2 billion. The proposed barricade is just one of many proposed projects to build seawalls, surge gates, levees, and other barriers to defend U.S. coastal cities in an era of rising seas and climate-fueled floods and storms. A proposed flood wall in Miami would cost federal taxpayers $8 billion.

Researchers generally agree that sea levels are likely to rise by at least 3 feet by the end of the century. Some experts believe the rise will be much greater. So, a key question is whether these barriers will actually keep out the water. Critics of many of the proposed solutions contend that they are doomed to fail.

Flooding has caused nearly $1 trillion worth of damage along the East and Gulf coasts over the past 40 years. And things are almost certain to get worse in Charleston and other coastal cities.

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Fortress Charleston: Will Walling Off the City Hold Back the Waters?

Photo, posted October 7, 2015, courtesy of Jeff Turner via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Utility-Scale Solar On The Rise

May 8, 2019 By EarthWise Leave a Comment

According to research from Goldman Sachs, utility-scale solar power capacity is expected to grow by double digits globally over the next two years. The growth will be driven by expanding use of the technology in the United States, Europe, the Middle East, and China.

Solar power is the world’s fastest growing source of electricity generation and is slowly taking market share from fossil fuels like coal and natural gas. The transition is being driven by a combination of continuously lower prices for solar power and the impact of policies aimed at reducing emissions.

Utility-scale solar is defined as installations designed solely to feed electricity into the grid, in contrast to smaller-scale residential or commercial building units. There are now solar farms larger than half a gigawatt in generating capacity. According to the Goldman report, global utility-scale solar installations will reach 108 gigawatts in 2019, up 12% over the previous year, and will then grow another 10% to 119 gigawatts in 2020.

When residential and other smaller installations are included, most analysts expect global solar power capacity to soon hit 600 gigawatts. To put this in perspective, the global capacity only reached 100 gigawatts in 2012 and was actually less than 10 gigawatts in 2007.

Even more dramatic than the growth of solar installations is the reduction in solar cost, and the two are obviously closely related. Solar panel costs have dropped from around $70 per watt of electricity generated in 1980 to 36 cents per watt currently in the United States. When favorable policies both from governments and related to corporate sustainability targets are added to the mix, the booming growth in solar power is easy to understand.

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Large-scale solar power set for double-digit growth: Goldman Sachs

Photo, posted March 7, 2019, courtesy of Hedgerow Inc 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.

Examining Sea Level Rise

January 17, 2019 By EarthWise Leave a Comment

It’s no secret that sea levels along the East Coast of the United States are rising. But what’s less known is that the water isn’t rising at the same rate everywhere. As the climate continues to change, some cities may remain dry while others struggle to keep water out.

During the 20th century, sea levels rose about 18 inches near Cape Hatteras in North Carolina and along the Chesapeake Bay in Virginia. During that same time period, New York City and Miami experienced a 12 inch sea level rise, while the waters near Portland, Maine only rose 6 inches. According to a study recently published in the journal Nature, there’s an explanation for this.

The variation is a result of a phenomenon called “post-glacial rebound.” During the last ice age, huge sheets of ice once covered land areas in the Northern Hemisphere, including parts of the Northeast U.S. The weight of the ice weighted down the land like a boulder on a trampoline. At the same time, peripheral lands such as the U.S. mid-Atlantic coast rose up. As the ice melted, the previously weighted-down regions rebounded while the peripheral lands began to sink. While these ice sheets disappeared some 7,000 years ago, this see-sawing of post-glacial rebound continues to this day.

Researchers combined data from GPS satellites, tide gauges, and fossils in sediment with complex geophysical models to produce this comprehensive view of sea level change since 1900. While post-glacial rebound accounts for most of the sea level variation along the East Coast, researchers noted that when that factor is stripped away, “sea level trends increased steadily from Maine all the way down to Florida.”

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Why is sea level rising faster in some places along the US East Coast than others?

Photo, posted August 24, 2014, courtesy of Bill Dickinson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving Venice From The Sea

January 26, 2018 By EarthWise Leave a Comment

The risks of rising sea waters are growing more apparent every year. While the world struggles with taking action to reduce the carbon emissions that are driving the sea level rise, cities around the world are building sea walls designed to protect them from storm surges and flooding. Most of these are massive, complex infrastructure projects that cost billions of dollars and take decades to complete.