SEARCH BLOG: CLIMATE
After reading the following in The Wall Street Journal, I contacted the author, Robert Lee Hotz, concerning the suppositions behind New York City's plan to avert inundation by 2080.
[image from the movie "The Day After Tomorrow"]
NEW YORK -- When major ice sheets thaw, they release enough fresh water to disrupt ocean currents world-wide and make the planet wobble with the uneven weight of so much meltwater on the move. Studying these effects more closely, scientists are discovering local variations in rising sea levels -- and some signs pointing to higher seas around metropolitan New York.
Sea level may rise faster near New York than at most other densely populated ports due to local effects of gravity, water density and ocean currents, according to four new forecasts of melting ice sheets. The forecasts are the work of international research teams that included the University of Toronto, the National Center for Atmospheric Research in Boulder, Colo., Florida State University and the University of Bristol in the U.K., among others.
His response:"Sea level is currently rising at 2.378 mm/year. At that rate, it will take 631 years for sea level to rise 1.5 meters. During that time hundreds of billions of people may have lived and died – the ultimate displacement."
2009/05/15/scientific-jargon- would-will-could-might-maybe/# more-7887
The problem with extrapolating short-term variations in climate is the absurdity of the results. For example, the spike in temperatures in the 1990s has been followed by a general cooling in the 2000s. In the U.S., as measured by temperature extremes, the present decade is wholly unremarkable...
If New York City [or any other coastal urban area such as New Orleans] wants to protect itself against sea surges, it is wholly unnecessary to justify it by bad science or science fiction. In a world with sufficient problems, it is foolish to create additional problems... and solutions... that will cost billions or trillions of dollars and accomplish very little. The Netherlands have shown that living with high seas can be accomplished with relatively simple efforts. There is significant doubt that New York City will be faced with that problem.
You would be correct in your estimate if the rate of increase remains the same. And that is, of course, the point of all the research on greenhouse gas emissions and global warming. The rate of change is increasing. How quickly it is changing is the argument. With sea level projections, we do know that sea level has risen alreday about one foot during the 20th Century in response to a combination of rising temperatures and, in some areas, land subsidence. To predict the future, the problem is complex because human behavior is the key variable in a range of best-case/worst-case scenarios. All these sea level rise figures are estimates and they all encompass a range of possibilities depending in part on which of the many greenhouse gas emissions scenarios we do or do not embrace.
In the direst scenario, in which both the Greenland ice sheets and the West Antarctic Ice Sheet completely melt, the global sea level could rise 32 feet or more over several centuries. Obviously that's the most extreme possibility and there's no way to know whether it is at all credible or just plain scare-mongering. New York planners have adopted a much more conservative set of parameters based on the best scientific advice they could get. Earlier this year, the city-appointed New York Panel on Climate Change released its formal prediction of how temperature, precipitation and sea level for the metropolitan area might change over the coming century. You can read that report and others by New York's planners on the local climate change and what they are doing about it at:You mention that the Netherlands lives with high seas "with relatively simple efforts." Not so simple, really. To prevent storm surge flooding, the Netherlands has built 1,500 miles of dikes, 120 miles of reinforced sea dunes, 3,748 miles of drainage canals, sea walls and flood control dams. To name just one part of the system, the Oosterschelde storm surge barrier is 5 1/2 miles long and is composed of 65 moveable piers that each measure up to 100 feet high and weigh 8,000 tons. It cost about $3.2 billion and it took 19 years to build.
[Excerpt from CLIMATE RISK INFORMATION - NEW YORK CITY PANEL ON CLIMATE CHANGE:]Rising sea levels are extremely likely. GCM-based
projections for mean annual sea level rise in New
York City are:
• 2 – 5 inches by the 2020s
• 7 – 12 inches by the 2050s
• 12 – 23 inches by the 2080s
Because GCMs do not capture all of the processes
which may contribute to sea level rise, an alternative
method that incorporates observed and longer-term
historical ice-melt rates is also included. This “rapid
ice-melt” approach suggests sea level could rise by
approximately 41 to 55 inches by the 2080s.
Your arguments are persuasive; however, the present data do not seem to justify the projections of increasing ice melt. While there has been some recent reduction of the northern hemisphere ice sheet [with a possible reversal in the last few years], the southern hemisphere has had a slightly opposite trend.The University of Illinois has a site that tracks polar ice in square miles... north and south poles. It does show a modest decline in ice over the past 40 years, including a recent decline which, in large part, NASA attributed to unusual wind conditions in the arctic and which has started to reverse.
You are correct that predicting the future is complex, especially when the analysis of present data is so difficult. I correspond ... with two well-known authors of climate information on the internet: Dr. Roger Pielke, Sr., climatologist; and Anthony Watts, meteorologist. Anthony tends to be a little dramatic in his arguments, but does back them up with data; Roger is more restrained and accepts that humans do influence regional climates, but primarily from land use changes, not by fractionally increasing CO2 in the atmosphere.
Regardless, I do not expect to alter your views regarding climate change. I do agree that there are actions we can take to lessen the impact on our climate and general environment. NYC plans to address worst-case scenarios are fine. Even spending $3.2 billion over 2 decades would be minuscule compared with costs of the city being inundated with a sudden surge of water from a hurricane... however remote the possibility. Their plans, however well intended, are based on some very shaky "science"... actually some very shaky computer modeling. Therefore, the fact that they have such plans adds no credibility to the projections.
- Anthony Watts - for example: Despite popular opinion and calls to action, the Maldives are not being overrun by sea level rise
- Climate Science - for example: Temporal Trends In Arctic and Antarctic Sea Ice Maximum and Minimum Areal Extents
My concern is that the Federal government is pushing forward with policies and programs that will have disastrous results for our economy in the name of preventing naturally-occurring changes to our climate. Energy independence from politically unstable or hostile sources is a worthwhile effort; restricting that effort in a narrow band of alternatives based on scare tactics is the height of stupidity. It is as if a person becomes ill and his temperature rises to 103° temporarily. Using projections from temperature trends would indicate rapid rises to 110° and beyond. Simplistic thinking about climate variation is more of a danger to us than real climate variations. Wet suits will not be the NYC fashion rage of 2080.
It is all well and good for NYC to have solid infrastructure plans and the link to the .pdf documents provided by Mr. Hotz [which I greatly appreciate] shows that NYC has done a significant amount of planning and implementation to manage an urban area that supports 8.5 million people.
It is unfortunate, in my opinion, that it is deemed necessary by NYC to justify such efforts with alarming projections similar to Al Gore's.