By Roger Straw, August 22, 2019
What’s to do about the possible 6-foot sea level rise along our Carquinez coast?
Actionable sea level rise is scientific consensus. This from the National Oceanic and Atmospheric Administration (NOAA)’s Climate.gov website:
NOAA scientists conducted a review of the research on global sea level rise projections, and concluded that there is very high confidence (greater than 90% chance) that global mean sea level will rise at least 8 inches (0.2 meter) but no more than 6.6 feet (2.0 meters) by 2100.
Some researchers have predicted worse. See What Does U.S. Look Like With 10 Feet of Sea Level Rise? where huge numbers of homeowners would be affected:
|Cities with the Most Population on Affected Land|
|1. New York City||703,000|
|2. New Orleans||342,000|
|4. Hialeah, FL||224,000|
|5. Virginia Beach||195,000|
|6. Fort Lauderdale||160,000|
|8. Stockton, CA
(Sacramento-San Joaquin Delta)
|9. Metairie, LA||138,000|
|10. Hollywood, FL||126,000|
An interactive map by ClimateCentral.org can be adjusted to show Benicia at various levels of sea level rise. Here we are at 6 feet:
The odds of reaching a 6 foot rise are good, given the slow pace of corporate and government action to slow global warming.
There is one single lifetime – 81 years – between now and the year 2100. What should Benicia city leaders be doing in anticipation of a 5 or 6 foot inundation of our shores? What should homeowners on Semple Crossing and everyone in lower downtown – all the way up to and including Rancho Benicia on East H Street – be doing?
I don’t have answers. But it’s a very real question….
‘We Should Be Retreating Already From the Coastline,’ Scientist Suggests After Finding Warm Waters Below GreenlandEcoWatch Jordan Davidson, Aug. 20, 2019
Andrew Yang’s assertion that people move away from the coast at the last Democratic debate is the completely rational and correct choice for NASA scientists in Greenland.
“There is enough ice in Greenland to raise the sea levels by 7.5 meters, that’s about 25 feet, an enormous volume of ice, and that would be devastating to coastlines all around the planet,” said Josh Willis, a NASA oceanographer, to CNN. “We should be retreating already from the coastline if we are looking at many meters [lost] in the next century or two.”
Willis and his research team at NASA’s Ocean Melting Greenland have been seeing some alarming patterns as they jet around the island’s coastline since heat waves bore down on the U.S. and Europe at the end of July, as CNN reported. Not only is the surface temperature warmer, turning Greenland into a slush-filled mess, but the ocean temperature deep under the water is also rising. The warming water eats away at the foundation of the glaciers, meaning Greenland’s massive ice sheet is getting weaker at the top and the bottom, which spells trouble for the entire world.
“Greenland has impacts all around the planet. A billion tons of ice lost here raises sea levels in Australia, in Southeast Asia, in the United States, in Europe,” said Willis to CNN. “We are all connected by the same ocean.”
The scientists looking at the ice and waters found a large opening of water near Helheim glacier, a huge 4-mile glacier on Greenland’s east coast, that had warm water along its entire depth, more than 2,000 feet below the surface, as CNN reported.
“It’s very rare anywhere on the planet to see 700 meters of no temperature variation, normally we find colder waters in the upper hundred meters or so, but right in front of the glacier it’s warm all the way up,” said Ian Fenty, a climate scientist at NASA, to CNN. “These warm waters now are able to be in direct contact with the ice over its entire face, supercharging the melting.”
Helheim has made news the past two summers. Two years ago it lost a huge 2-mile piece. Last summer a chunk the size of lower Manhattan broke off and was captured on video, as National Geographic reported.
This year the glacier has continued to melt.
“It retreats by many meters per day, it’s tens of meters per day. You can probably set your iPhone on timelapse and actually see it go by,” said Willis to CNN.
The ice in Greenland started the summer weak. There was little snowfall this past winter to reinforce the ice or to absorb the sunlight in the peak of summer, when the sun never fully goes down. Fresh snow stays bright and reflective, which bounces away solar radiation. Older snow is less reflective and absorbs the sun’s heat. When the first heat wave hit in June, 45 percent of Greenland’s ice sheet was ready to melt, according to National Geographic.
Arctic ice like Greenland’s is also vital to removing carbon from the atmosphere, according to a study in the journal Polar Biology. The calcium carbonate crystals that make up sea ice trap carbon dioxide in a cold brine. When the sea ice melts, it drops that carbon dioxide into the ocean where it binds to algae, which stops it from circulating around the atmosphere.
As sea ice decreases, less carbon will be removed from the atmosphere. Plus, the melting ice will raise sea levels. Glaciers like Helheim are big enough to make global sea levels rise by one millimeter in just one month, which concerns scientists, as CNN reported.
Greenland Temps Soar 40 Degrees Above Normal, Record Melting of Ice Sheet https://t.co/I3iD1aj1mO
— The YEARS Project (@YEARSofLIVING) June 19, 2019