Skip to comments.Superstorm Sandy and Sea Level Rise
Posted on 12/04/2012 9:37:47 PM PST by ExxonPatrolUs
Climate.govs Brian Kahn interviews Cynthia Rosenzweig, a climate impacts expert at NASA Goddard Institute for Space Studies, co-chair of the New York City Panel on Climate Change, and director of the NOAA-sponsored Consortium for Climate Risk in the Urban Northeast.
Why should New Yorkers care about sea level rise?
First of all, sea level rise is a big issue for millions of people in the U.S., not just New Yorkers. Twenty-three of the 25 most densely populated U.S. counties are on the coast. In New York, the full brunt of Hurricane Sandy has shown how powerful and damaging the effects of coastal flooding can be for infrastructure and communities.
The storm itself we cant immediately link to climate change, but the flooding damage we can. As sea levels continue to rise, a storm of the same magnitude will cause even greater damages due to storm surges coming in on top of a higher baseline water level.
What kind of sea level rise has New York Harbor seen over the past century?
Weve had roughly a foot of sea level rise in the New York City area in the past century. Thats measured at a tidal gauge near Battery Park just off the southern tip of Manhattan.
The majority of the sea level rise in the New York City region is due to global warming: primarily, because of thermal expansion of ocean water as it warms and secondly, melting of land-based ice sheets.
Land subsidence [sinking] in the New York City area has been roughly 3-4 inches per century, which is primarily due to the Earths crust rebounding* from being compressed by massive ice sheets that covered Canada and the northern U.S. about 20,000 years ago near the end of the last Ice Age. Local variations in ocean surface elevation associated with the strength of the Gulf Stream has played a small role as well.
How do sea level rise and storm surge interact?
Sea level rise is like a set of stairs. The 12-inch increase in New York Harbor over the last century means weve already gone up one step. When a coastal storm occurs, the surge caused by the storms winds already has a step up, literally. For Sandy, that meant greater coastal flooding in New York and the surrounding region than we would have experienced a century ago. Continuing to climb the staircase of sea level rise means well see greater extent and greater frequency of coastal flooding from storms, even if storms dont get any stronger.
How does sea level rise in New York Harbor compare to other parts of the U.S.? What about the global average?
Sea level isnt rising evenly throughout the world. On average, global sea level has risen about eight inches since 1880. So, the New York rate of sea level rise of nearly one foot is higher than the global average rate. In the U.S., rates of change vary. For example, Grand Isle, Louisiana near New Orleans has seen sea level increase by 23 inches since 1947 whereas Seattle, Washington, has only seen about six inches over that same period. Local factors such as land subsidence are primarily responsible for the differences.
Whats the range of sea level rise we can expect to see in the future for the New York region?
Weve created two sets of sea level rise projections for the region by downscaling global climate models for local conditions. Using a similar approach to the last IPCC [Intergovernmental Panel on Climate Change] report, we project 12-23 inches by the 2080s.
We also developed a rapid-ice-melt scenario, based on the same greenhouse gas concentrations, but factoring in observations of accelerated ice sheet melt and paleoclimate data from ice cores, tree rings, and other sources. That projection gives a higher end of 41-55 inches in the 2080s.
Sea levels began to rise 18k years ago at the end of the last glacial period. They have risen about 135 meters since then which is an average of 7.5 millimeters per year. That is an average of 750 mm per century (29.5 inches) which is far more than the average over the last century.
From 1880 to 2000 sea level rose about 20 cm or just under 8 inches. Far far less than the nearly 30 inches per century average over the last 18,000 years.
Not exactly climatologist credentials.
Refuse to be taken in by the new packaging, "climate change". The original claim of these con-artists and loons was that the "globe is warming". Hold their feet to the fire. I refer to them only as "Global Warmers" and will never accept their new identification of "Climate Changers".
Not sure who's the bigger moron here, Brian Kahn or Cynthia Whatsherface.
This paragraph reads like a pseudo-scientific concept as filtered through the brain of a first grader.
By definition, "rebound," as it relates to glaciers, means the ground rises, and, relatively, the sea level falls, which is the direct opposite of what is being presented as science.
A serious disconnect between reality and activism.
That, and the fact that they now admit to making their analysis by using the thoroughly discredited computer models that have not even remotely proven themselves. Garbage in, garbage out.
Real scientists have forced the IPCC to cease and desist calling reults of computer models "predictions." You'd think that should make them go out and buy a little humility and anti-ignorance pills.
But, no, they now call them "extrapolations." Which the ignorant assume is a serious and wisdom-laden concept, when it actually means "SWAG."
Reading Mark Twain's proof that the length of the Mississippi River is relentlessly getting shorter is a funnier version of the snake oil these charlatans are trying to sell.
Is it high tide or low tide?
“Torture the data long enough and hard enough and it will always confess” - Dr. Earl R. Rich.
One must hope this Data Dominatrix is blond, as she will need an excuse for making a statement “...’of such overt unreality that one fears it will discredit her science’..”. My apologies to Professor Linzden of MIT for the slight liberties I took with his well known sentence about Global Warmers.
Dr. Data Dominatrix is tricky, indeed, when she attempts to use isostatic rebound to predict climate changes caused by anthropogenic global warming. A similar ruse was tried when other Global Warmers claimed England was “sinking into the sea at an alarming rate”.
The ends were, but the middle was rising. Those busy torturing the data in furthering their grant funding attempts know full well that when an island is loaded with several thousand feet of ice during an ice age, that melting of the ice causes the interior/center of the island to rise and the ends to submerge as the land mass straightens out from being bent in the middle by the accumulated weight of the glacial ice.
Basic science being misrepresented by those unable to secure funding to support them in the halls of the academented.
Shameful! Shameful, indeed.
They continue to expect reasonable people to ignore the laws of physics. In this case the "Law of Equilibrium" is being violated. How can the earth experience different levels of ocean rise? I don't buy it.
“Local factors such as land subsidence are primarily responsible for the differences.”
This last sentence basically says that the sinking of coastal land is happening at different rates. I think someone told the global warming crowd that nobody believes the sea level is rising more in Venice Italy than in other parts of the world because it defies logic; when I fill my tub the end by the spigot doesn’t fill before the other end.
Cyrrently sea level is “higher” in the west pacific than along the west coast. The difference is due to the trade winds blowing west and mounding up warm water. When the trade winds relax that warm water spills east and we get El Nino. The differences caused by wind make it difficult to measure sea level.
Well i actually believe the ocean levels are rising but It’s damn sure not because of global warming, it’s called erosion I see it every time it rains here on the ranch. The run off from the rains wash sediment into my stock ponds and periodicly I have to dredge them back out. The Mississippi dumps about 500 million metric tons of sediment into the gulf every year. Now lets throw in all the other rivers and streams of the world, beach erosion and sediment that settles from the air and it’s going to add up and displace alot of water. Drop enough BB’s in a fish tank and it will overflow.
” By definition, “rebound,” as it relates to glaciers, means the ground rises, and, relatively, the sea level falls, which is the direct opposite of what is being presented as science.
A serious disconnect between reality and activism.”
Picture dropping a stone in a pond. The stone sets off ripples with the water first rising at the place you dropped the stone. However, the next “ring” of the wave has the water dropping. The net water level doesn’t change, you just have areas of rebound adjacent to areas of subsidence.
The earth under the icecap rebounded when the ice age ended. However, the earth in the next “ring” out, i.e NY, and parts of northern Europe, subsided.
Here’s a map.