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Record low Antarctic sea ice

October 30, 2023 By EarthWise Leave a Comment

Antarctica’s winter came to a close in September and during that month, the continent reaches its maximum amount of sea ice that grows during the darkest and coldest months. This year, that maximum occurred on September 10th and turned out to be the lowest on record.

The sea ice around Antarctica reached a maximum extent of 6.5 million square miles according to NASA researchers. That was nearly 400,000 square miles below the previous record low set in 1986.

There are several possible causes for the meager growth of Antarctic sea ice this year. It may be a combination of several factors including El Niño, wind patterns, and warming ocean temperatures. Recent research indicates that ocean heat is most likely playing an important role in slowing ice growth in the cold season and enhancing ice melting in the warm season.

The record-low ice extent so far this year is a continuation of a downward trend in Antarctic sea ice that has gone on since the ice reached a record high in 2014. Prior to that year, the ice surrounding the southern continent was actually increasing slightly by about 1% every decade.

Meanwhile, Arctic sea ice reached its minimum extent in September and it was the sixth-lowest level in the satellite record. Scientists track the seasonal and annual fluctuations of polar sea ice because they shape polar ecosystems and play a significant role in global climate. Sea ice melting at both poles reinforces global warming because bright sea ice reflects most of the Sun’s energy back to space while open ocean water absorbs 90% of it.

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Antarctic Sea Ice Sees Record Low Growth

Photo, posted June 30, 2023, courtesy of Pedro Szekely via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Great Salt Lake Is Disappearing | Earth Wise

August 31, 2022 By EarthWise Leave a Comment

Utah’s Great Salt Lake is the largest saltwater lake in the western hemisphere. According to data from the US Geological Survey, the surface water elevation of the Great Salt Lake has fallen to the lowest level since records began in the mid-1800s. The average elevation is now 4,190 feet above sea level. With this drop in water level, the surface area of the lake is little more than half of its historical size. The lower water level has exposed about 700 square miles of previously submerged lakebed.

The lake now contains about a quarter of the volume of water that it did at its high point in 1987. The precipitous drop in water is a result of water usage from the lake coupled with climate change-fueled drought. Increased water demand is due to the rapidly growing population of metropolitan Salt Lake City. Utah’s population is projected to increase by almost 50% by 2060.

The Great Salt Lake goes though seasonal cycles of water loss and replenishment. Rain and snow generally refill its level. However, because of the ongoing megadrought in the West, water evaporation and depletion continue to exceed the amount of water entering the lake. The water levels are expected to further decrease until fall or early winter, when incoming water is expected to equal or exceed evaporation.

The decline of the Great Salt Lake is a serious threat to the economy, ecology, and people of northern Utah. The lake generates snowpack, is a refuge for hundreds of migratory birds and other wildlife and generates millions of dollars in the economy through mineral extraction and tourism.

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Utah’s Great Salt Lake is disappearing

Photo, posted October 6, 2020, courtesy of Julie Girard via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rising Seas In The Maldives | Earth Wise

May 24, 2021 By EarthWise Leave a Comment

The Republic of Maldives is an archipelago in the Indian Ocean, southwest of Sri Lanka and India and about 400 miles from the Asian mainland. It is one of the world’s most geographically dispersed sovereign states, the smallest Asian country by land area, and, with a little over 500,000 inhabitants, the second least populous country in Asia. With its spectacular scenic beauty, it is also a premier tourist attraction.

With more than 80% of its 1,190 coral islands standing less than 1 meter above sea level, the Maldives has the lowest terrain of any country in the world. As a result, the Maldives is particularly vulnerable to the sea level rise associated with climate change.

Some studies predict a grim future for the Maldives as well as other low-lying islands. One study concluded that the islands could become uninhabitable by 2050 as wave-driven flooding becomes more common and freshwater becomes limited.

The Maldives government has explored plans to purchase land on higher ground in other countries. Planners are also working to enhance the resilience of the country’s current islands. An example is Hulhumalé, a newly constructed artificial island northeast of the country’s capital, Malé.

Construction of Hulhumalé began in 1997 and it now covers 1.5 square miles, making it the fourth largest island in the Maldives. Its population is now more than 50,000, with more than 200,000 expected to eventually move there. The new island, built by pumping sand from the seafloor onto a coral platform, rises about 2 meters above sea level. The extra height could make the new island a refuge for Maldivians driven off lower-lying islands by the rising seas.

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Preparing for Rising Seas in the Maldives

Photo, posted June 15, 2009, courtesy of Elena N via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Record Low Ice In The Bering Sea | Earth Wise

January 30, 2020 By EarthWise Leave a Comment

The Bering Sea is the area of the far northern Pacific Ocean that separates Alaska from Russia. Sea ice in the Bering Sea shrank to its lowest levels in recorded history in 2018, an event with profound effects on northwest Alaska residents who depend on marine resources for food, cash, and culture.

The loss of ice is indicative of very rapid change in the entire northern Bering Sea ecosystem with ramifications for everyone in the region. A new peer-reviewed study published in the Bulletin of the American Meteorological Society examined the details and consequences of the drastic changes in the Bering Sea.

The study found that the maximum daily Bering Sea ice was the lowest on record, and the widespread impacts of that fact include unprecedented weather effects, marine wildlife die-offs, and sightings of animals outside of their normal range. Ecological changes included the first documented mass strandings of ice-associated seals, a redistribution of thermally sensitive fish, and a multispecies die-off of seabirds due to starvation.

Persistent and anomalous warm winter weather contributed to poor ice conditions that resulted in a fatal accident on an ice road and retreating and fractured sea ice led to ice-laden flooding that caused power outages and infrastructure damage. In addition, there have been more than 50 reports of unusual events related to weather and marine wildlife.

The record-low sea ice is a consequence of the warming climate resulting in a warmer ocean, later arrival of sea ice, and more frequent storms than in the pre-industrial era. These conditions are continuing to increase in occurrence.

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Record low level of Bering Sea ice causes profound, widespread impacts

Photo, posted April 7, 2014, courtesy of Allen Smith via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.