salty

The Scourge Of Salt | Earth Wise

June 10, 2022 By EarthWise Leave a Comment

Rising seas are increasing saltwater intrusion on land and rising temperatures are causing greater evaporation. The result is mounting levels of salt in waters and in soils.

Rising sea levels cause salty ocean water to push further into river deltas. There is already a surge in saltiness across all inhabited continents. Seawater works its way further upstream when dams hold back water. Pumps that remove fresh water from underground sources for irrigation and drinking supplies add to the problem. In dry regions, irrigation systems delivering water to crops increasingly bring salt onto fields.

People add to the problem by pouring saline drainage water from mines into rivers and by using salt to de-ice roads in the winter.

A modeling study pinpointed hotspots for climate change-induced salinization in numerous locations including the U.S. Southwest, wide areas of Australia, Mexico, South Africa, Brazil, central India, northern China, and more.

Some ecosystems are adapted to saline environments but major alterations in the balance between saline and fresh water is creating growing problems for ecosystems, lake fisheries, crop growing, and even human health.

The damage caused by salt is likely to be so severe that salinization will become a major cause of environmental refugees when the land they live on can no longer sustain them.

Salt will be a growing threat to the world’s food supplies, especially where farmers depend on artificial irrigation. About a third of the world’s food is grown in irrigated fields, and a fifth of those fields are deemed to already be salt-contaminated. Ultimately, only a halt to climate change will be capable of combatting the scourge of salt.

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Salt Scourge: The Dual Threat of Warming and Rising Salinity

Photo, posted June 3, 2017, courtesy of Jason Jacobs via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Coastal Northeast Is A Hotspot | Earth Wise

November 16, 2021 By EarthWise Leave a Comment

Global warming is, obviously, a world-wide phenomenon. When the concept of a 2 degrees Celsius temperature rise is discussed, it refers to the average global temperature and the effects that would have on such things as sea level rise and weather patterns. But the effects of the changing climate are not homogeneous. Very different things can happen and are happening in different places.

One such place is the coastal northeastern United States, which is a global warming hotspot. The region is heating faster than most regions of North America and, indeed, 2 degrees of summer warming has already happened in the Northeast.

New research led by the University of Massachusetts Amherst has determined that this heating is linked to significant alterations in the ocean and atmospheric conditions over the North Atlantic.

Several studies have found that the Atlantic Meridional Circulation is slowing down. The AMOC conveys warm, salty water from the tropics north towards Greenland, where it cools and sinks. The cooled water than flows back south as deep-water currents. As the warming climate melts glaciers in Greenland, the circulation slows down, less cooled water arrives in the south, and there is more heating of the ocean off the Northeastern coast.

At the same time, the North Atlantic Oscillation, a weather phenomenon that governs the strength and position of the winds that blow from the U.S. over the Atlantic, has tended to settle into a pattern that enhances the influence of ocean air on the eastern seaboard climate. Warmer ocean air being blown over the region has led to rising temperatures in Boston, New York, and Providence, Rhode Island.

As the average temperature of the world rises, some places will warm more quickly and others more slowly.

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The Coastal Northeastern U.S. Is A Global Warming Hotspot

Photo, posted August 8, 2010, courtesy of Doug Kerr via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Cooling The Earth With A Warmer Arctic | Climate Change | Earth Wise

January 24, 2020 By EarthWise 1 Comment

Researchers are considering a wide range of approaches to mitigate the effects of global climate change. Among these are various strategies of geoengineering, which must be viewed with enormous caution, given the high likelihood of unintended consequences from almost anything we might do.

Researchers at the International Institute for Applied Systems Analysis have investigated potential strategies for cooling the planet in the absence of Arctic sea ice.

The Arctic region is heating up faster than any other place on earth and its sea ice is rapidly disappearing. Estimates are that summer sea ice in the Arctic Ocean will be largely gone within a generation. Arctic ice and snow reflect the sun’s energy into space, which helps to keep the planet cool. What happens if that ice is gone?

The researchers explored the fact that the Arctic Ocean ice actually insulates the Arctic atmosphere from the warmer water under the ice. Without the ice layer, the surface water would actually increase air temperatures by 20 degrees C during the winter. That in turn would increase the heat irradiated into space and thereby cool down the planet.

The Arctic sea ice is in part maintained because the upper regions of the Arctic Ocean have lower salinity than the Atlantic Ocean. This stops Atlantic water from flowing above the cold Arctic waters. So, if we were to somehow deliberately increase the salinity of the Arctic Ocean surface water, warmer, less salty Atlantic Ocean water would flow in, increase the temperature of the Arctic atmosphere, and release heat trapped in the ocean into space.

It all sounds pretty crazy, but the researchers say that given the seriousness of climate change, all options should be considered when dealing with it.

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Could we cool the Earth with an ice-free Arctic?

Photo, posted August 19, 2016, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving The Sea From Salt

July 18, 2016 By WAMC WEB

The Persian Gulf along with the Red and Mediterranean seas are getting saltier all the time because of the waste products of desalination. The United Arab Emirates, Saudi Arabia, Kuwait, Qatar, Bahrain and Oman account for 45% of the world’s desalination capacity. And the byproduct of desalination is brine, which is twice as salty as seawater. Even advanced desalination plants produce two cubic meters of waste brine for every one cubic meter of clean water.