Coastal homes are threatened by sea level rise


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Beautiful sea front property is being threatened by sea level rise. (flickr/sdobie)

Eden DeWald | June 20th, 2018

Coastal homes all the way from Maine to Florida are feeling the threat of sea level rise. Approximately 300,000 homes along the East and West Coast of the United States are at risk for reoccurring flooding due to sea level rise. According to National Geographic, the global mean sea level has risen four to eight inches over the past century. However, the rate at which sea level is rising has been twice as fast for the last 20 years when compared to the first 80 years of the last century.

Sea level rise is caused by three main factors, all of which are consequences of climate change. Thermal expansion, the melting of ice over Antarctica and Greenland, and the melting of polar ice caps and glaciers, all contribute to the measurable rise that researchers have observed over the past century. In 2012, The Intergovernmental Panel on Climate Change predicted that sea level could rise up to 38 inches by 2100.

Sea level rise has serious consequences for homeowners. By 2045, the slowly creeping disaster of chronic flooding could pose great threats to coastal housing markets. The Union of Concerned Scientists conducted a study on the effect that sea level will have on the East Coast and the Gulf area. Kirsten Dahl, an author of the study, stated that the loss of tax revenue from affected homes could cut the tax base of small towns by as much as 70 percent. Coastal homes are highly sought after real estate, but buying a beach house may not be the luxury it once was.

 

Record high winter temperatures in Arctic, again


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The Rink Glacier in Greenland captured melting into the sea during the summer of 2012. (NASA/Flickr)
Jenna Ladd | March 8, 2017

The data is in, and winter temperatures in the Arctic reached record highs again this year.

U.S. weather data shows that average temperatures during December, January, and February this year were 8.8 degrees Fahrenheit warmer than usual. There are fifteen weather monitoring stations throughout the Arctic, many of them in Alaska and Greenland. Winter temperatures in some regions soared higher than the average. Barrow, Alaska, for example, sizzled with average winter temperatures a full 14 degrees Fahrenheit above normal.

Even the weather monitoring station that is located closest to the top of the world in northern Greenland recorded 60 hours of above freezing temperatures this winter. Prior to this winter, scientists say, the station had only experienced above-freezing temperatures during February a few times in history.

The rising temperatures caused sea ice to vanish in the North Pole again this year. North Pole sea ice coverage hit a record low in February 2017 and decreased again this year by a full 62,000 square miles, which is about the size of the state of Georgia.

Ruth Mottram is a climate scientist at the Danish Meteorological Institute. She said to the Associated Press, “The extended warmth really has kind of staggered all of us.”

Some scientists have pointed to melting sea ice as an explanation for the extreme and strange winter weather that has plagued the eastern United States this year. Simply put, less sea ice means that there is less of an atmospheric pressure difference between the Arctic and areas further south, which weakens the jet stream. A weak jet stream causes  storms to linger over regions in the eastern U.S. and Europe before moving along, often making them more destructive.

State of the Climate Report reveals more than just temperature


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A global map depicting the difference from 2016 when compared to temperatures from 1981-2010. (NOAA, State of the Climate)
Jenna Ladd| August 24, 2017

2016’s position as the hottest year on record has been widely reported, but many other important, albeit terrifying, climate change milestones were achieved last year according to the State of the Climate Report published in the American Meteorological Society Bulletin.

The report, which is spearheaded by top editors from the National Oceanic and Atmospheric Administration (NOAA) National Centers for Environmental Information, has been described as a comprehensive annual physical for the planet. This year’s check up brought some bad news.

To begin, levels of carbon dioxide in the atmosphere reached a record high. The increase from 2015 to 2016 of 3.5 ± 0.1 parts per million was the largest jump in one year on modern record.

Drought was also widespread in 2016. During every month of the year, at least twelve percent of the global area was experiencing drought conditions. More than half of the land south of equator experienced drought conditions during some part of 2016.

2016 was the sixth year in a row when global sea levels were higher than the year before. In fact, global sea levels were 3.5 inches higher last year than they were in 1993. This sea level rise is attributed to alpine glacial melt; 2016 marked the 37th year in a row during which alpine glaciers retreated worldwide.

So far, 2017 is on track to bring more of the same, despite the absence of El Niño event.

 

On The Radio – Pace of sea level rise tripled since 1990


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A new study found that sea levels are rising nearly three times faster than in previous centuries. (Chris Dodd/flickr)
Jenna Ladd| June 12, 2017

This week’s On The Radio segment discusses a recent study that found sea levels are rising at a significantly faster rate than in the past. 

Transcript: Scientists, in a new study, have found that the Earth’s oceans are rising nearly three times as quickly as they were throughout most of the 20th century.

This is the Iowa Environmental Focus.

This new finding is one of the strongest indications yet that a much-feared trend of not just sea level rise, but its acceleration, is now underway.

Their paper, published in May’s Proceedings of the National Academy of Sciences, isn’t the first to find that the rate of rising seas is itself increasing — but it finds a bigger rate of increase than in past studies.

The new paper concludes that before 1990, oceans were rising at about almost a half an inch per decade. From 1993 through 2012, though, it finds they rose by almost one and a quarter inches per decade.

To learn more about the study, visit iowaenvironmentalfocus.org.

From the UI Center for Global and Regional Environmental Research, I’m Betsy Stone.

Iowa State researchers receive grants to improve glacier flow models and sea level predictions


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                         Calving of the Aialik Glacier in Kenai Fjords National Park in Alaska. (Alaska National Park Service)
Jake Slobe | February 15, 2017

Iowa State University’s Neal Iverson and a team of researchers are working on research that will predict how much glaciers will contribute to the rise of sea levels.

The research will focus on the extent to which glacier-flow to oceans is likely speed up over the next century as the climate warms.

Iverson, an Iowa State University professor of geological and atmospheric sciences who has studied glaciers in Iceland and Norway, and the rest of the research team will look to lab experiments and field work to build more realistic computer models of glacier flow.

Iverson said about the project:

“Glaciologists are trying to predict how fast glaciers will flow to the oceans. To do that, we need new lab and field data to include complexity in models that is usually neglected. These are complicated systems. Modeling them is hard. But we need to include how water in ice affects its flow resistance, and we need sliding laws that are based on the real topography of glacier beds and that include rock friction. Adding these things really matters.”

Two new grants will help Iverson and his team fund their research, both of which grants are from the National Science Foundation.  The research will also receive funding from the United Kingdom’s Natural Environment Research Council to support the work of applied mathematicians at the University of Oxford in England.

Iverson is the lead investigator on both grant proposals. The other researchers are Lucas Zoet, an assistant professor at the University of Wisconsin-Madison and a former postdoctoral research associate at Iowa State; Ian Hewitt, an associate professor and university lecturer at Oxford’s Mathematical Institute; and Richard Katz, a professor of geodynamics at Oxford.

The first project will look at temperate ice, or ice at its melting point, and how this soft, watery ice resists deformation. That’s important because the resistance to deformation of temperate ice at the edges of ice streams – areas of rapid ice flow within the Antarctic ice sheet that can be hundreds of miles long and tens of miles wide – holds back the flowing ice.

The second project will support development of better “sliding laws” to help predict the sliding speeds of glaciers and ice sheets. Sliding laws are the mathematical relationships between the glacier sliding speed and the factors that control it, such as the stresses below the glacier, the water pressure there, the topography of the glacier bed and the concentration of debris in glacier ice.

Both projects will use the glacier sliding simulator Iverson has been using since 2009 to study glacier movement.

The new projects will add complexity to Iverson’s lab experiments. Debris, for example, will be added to the ice ring to study friction between it and the rock bed during sliding. In other experiments, temperate ice will be sheared between rotating plates to study how its resistance to flow depends on its water content.

NPR: “Ready — Or Not. Abrupt Climate Changes Worry Scientists Most”


Photo by Rob Baxter; Flickr

 

An expert panel at the National Academy of Sciences is calling for an early warning system to alert us to abrupt and potentially catastrophic events triggered by climate change.

The committee says science can anticipate some major changes to the Earth that could affect everything from agriculture to sea level. But we aren’t doing enough to look for those changes and anticipate their impacts.

To read more and to listen to the audio, head over to NPR.