(Rates of global sea level rise continue to quicken. This has resulted in worsening tidal flooding for coastal cities like Miami, Charleston, New Orleans and Virginia Beach. Image source: Ice Melt, Sea Level Rise, and Superstorms.)
Sea Level Rise and Worsening Extreme Rainfall are Already Causing Serious Problems
Higher rates of precipitation from thunderstorms are becoming a more common event the world over as the hydrological cycle is amped up by the more than 1 degree Celsius of temperature increase that has already occurred since 1880. And when these heavy rainfall amounts hit coastal cities that are already facing rising seas, then pumps and drainage systems can be stressed well beyond their original design limits. The result, inevitably, is more flooding.
(Dr Eric Rignot, one of the world’s foremost glacial scientists, discusses the potential for multimeter sea level rise due to presently projected levels of warming in the range of 1.5 to 2 C by mid to late Century.)
New Orleans itself is already below sea level. And the land there is steadily subsiding into the Gulf of Mexico. Add sea level rise and worsening storms on top of that trend and the crisis New Orleans faces is greatly amplified.
Presently High and Rising Atmospheric Carbon Levels Imply Ultimately Catastrophic Sea Level Rise — How Soon? How Fast? Can We Mitigate Swiftly Enough to Prevent the Worst?
Presently, atmospheric carbon forcing is in the range of 490 parts per million CO2 equivalent. This heat forcing, using paleoclimate proxies from 5 to 30 million years ago, implies approximately 2 degrees Celsius of warming this Century and about 4 degrees Celsisus of warming long term. It also implies an ultimate sea level rise of between 60 and 180 feet over the long term. In other words, if atmospheric carbon levels are similar to those seen during the Miocene, then temperatures are also ultimately headed for those ranges. Soon to be followed by a similar range of sea level rise. In the nearer term, 1.5 to 2 C warming from the 2030s to late Century is enough to result in 20 to 30 feet of sea level rise.
(Antarctic ice loss through 2016. Video source: NASA.)
That said, warming and related sea level rise will tend to take some time to elapse. And the real question on many scientists’ minds is — how fast? Presently, we do see serious signs of glacial destabilization in both Greenland and West Antartica. These two very large piles of ice alone could contribute 34 feet of sea level rise if both were to melt entirely.
Meanwhile, East Antarctica has also recently shown some signs of movement toward glacial destabilization. Especially in the region of the Totten Glacier and the Cook Ice Shelf. But rates of progress toward glacial destabilization in these zones has, thus far, been slower than that seen in Greenland and West Antarctica. Present mass loss hot spots are in the area of the Thwaites Glacier of West Antarctica and around the western and southern margins of Greenland.
(Greenland ice loss through 2016. Video source: NASA.)
With global temperatures now exceeding 1 C and with these temperatures likely to exceed 1.5 C within the next two decades, it is certain that broader heat-based stresses to these various glacial systems will increase. And we are likely to see coincident melt rate acceleration as more glaciers become less stable. The result is that coastal flooding conditions will tend to follow a worsening trend — with the most vulnerable regions like the U.S. Gulf and East Coasts feeling the impact first. Unfortunately, there is risk that this trend will include the sudden acceleration of various glaciers into the ocean, which will coincide with rapid increases in global rates of sea level rise. In other words, the trend for sea level rise is less likely to be smooth and more likely to include a number of melt pulse spikes.
Such an overall trend including outlier risks paints a relatively rough picture for coastal city planners in the 1-3 decade timeframe. But on the multi-decade horizon there is a rising risk that sudden glacial destabilization — first in Greenland and West Antarctica and later in East Antarctica will put an increasing number of coastal cities permanently under water.
Rapid Mitigation Required to Reduce Risks
The only way to lower this risk is to rapidly reduce to zero the amount of carbon hitting the atmosphere from human sources while ultimately learning how to pull carbon out of the atmosphere. The present most rapid pathway for carbon emissions reductions involves an urgent build-out of renewable and non-carbon based energy systems to replace all fossil fuels with a focus on wind, solar, and electrical vehicle economies of scale and production chains. Added to various drives for sustainable cities and increasing efficiency, such a push could achieve an 80 percent or greater reduction in carbon emissions on the 2-3 decade timescale with net negative carbon emissions by mid Century. For cities on the coast, choosing whether or not to support such a set of actions is ultimately an existential one.
Ik kwam zojuist mijn oude vriend, de bestseller-auteur en mainstream-opiniemaker Geert Mak in de regen op straat tegen. Na elkaar te hebben begroet, vertelde Geert mij dat hij van oordeel is dat Europa zo snel mogelijk met Rusland om de tafel moet gaan zitten, om de opgelopen spanningen te deëscaleren. De VS heeft heel andere belangen dan 'wij,' aldus Mak, die benadrukte dat de macht van 'onze' Atlantische bondgenoot ingrijpend aan het afnemen is. Kortom, ik hoorde wat ikzelf al enige jaren op mijn weblog schrijf. Opvallend hoe een Nederlandse opiniemaker binnen zo'n betrekkelijk korte tijd zo wezenlijk van oordeel kan veranderen. Immers, Mak’s gevaarlijke anti-Rusland hetze was een treffend voorbeeld van zijn opportunisme. Mei 2014 beweerde op de Hilversumse televisie de zogeheten ‘chroniqueur van Amsterdam, Nederland, Europa en de VS,’ dat er sprake was van een 'Russische gevaar,’ aangezien ‘meneer Poetin’ aan ‘landjepik’ deed en dat de Russische president d…
A sign marks the entrance to White Earth Indian Reservation in Mahnomen County, Minn. (J. Stephen Conn / CC 2.0)
WHITE EARTH RESERVATION, Minn.—Candice (not her real name) awoke with a start. Someone was pulling down her sweatpants. It was a male friend.
“Stop!” she shouted.
He kept groping her. She kicked him and he fell off the bed. She dashed out of the bedroom, tripping and tumbling down the stairs. Gripped with fear, she heard his footsteps behind her in the dark and forced herself to stand upright as she staggered out to the porch.
Candice was still intoxicated. She got into her car and drove into a ditch. A white police officer pulled up. She struggled to hold back tears as she told him about the attempted rape.
All the officer saw was a drunk and disorderly Native American woman. He dismissed Candice’s report of sexual assault as a lie she had made up to avoid getting a DUI. He did not take her to the hospital for a forensic exam. The sexual assault was not recorded in his pol…