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The EPA report also allows decision makers to determine when a specified amount of sea level rise is likely happen. For example, in Washington DC, there is a 1 percent chance of a one foot rise in sea level by 2025, a 45 percent chance by 2050 and a greater than 90 percent chance by 2100.

Finally, estimates of sea level rise vary substantially by locality. For example, by 2100 there is a 50 percent chance that the sea will rise: by 13 Inches in Los Angeles, CA; by 20 inches in Miami Beach, FL; by 27 inches in Atlantic City, NJ; by 38 inches in Galveston, TX; and by 55 inches in Grand Isle, LA. This information can help coastal zone managers and others make better informed and more cost-effective decisions to protect coastal areas and structures, personal property, and coastal wetlands.

EPA results and consistency with IPCC estimates

I would like to note the good agreement and general consistency between the EPA and IPCC sea level rise estimates. The differences lie in that the EPA report estimates probabilities associated with various increases in sea level, whereas the IPCC report provides a lower, upper and best estimate, not in the overall fining of sea level rise.

The EPA report estimates a 50% chance of sea levels rising 18 inches (45 cm) by the year 2100. The best estimate by the IPCC is for 19 inches (49 cm). IPCC also reports a "high" estimate of a 34 Inch (86 cm) rise. The EPA report attaches probabilities of

10% and 1%, respectively, to its estimates of a 29 and 44 inch (75 cm and 112 cm) rise, bounding the IPCC high estimate. We are in close agreement with IPCC's "low" estimate of an 8 inch (20 cm) rise, for which we estimate a "high likelihood" probability of 90%.

Both the IPCC and the EPA reports note that the latest central estimates of sea level rise are lower than previous estimates, primarily due to lower estimates of global temperature change. We should also keep in mind that the range of uncertainty which surrounds these estimates is narrower. The science is improving, increasing our confidence in estimates of future sea level rise.

I would like to stress that there are significant impacts even with these newer estimates.

For example, a one-foot rise in sea level in 2100 would result in the following impacts to the Atlantic and Gulf coasts:

20-30% of coastal wetlands would be lost;

Sandy beaches would be eroded 100-150 feet;

Along developed estuarine shores such as the Chesapeake Bay, most beaches

would be replaced by bulkheads;

Along ocean shores such as the Outer Banks, beaches would require

nourishment and/or beach homes would be lost; and

How EPA did the Report

Perhaps as important as why EPA did the report is how EPA did the report. Using existing models, (e.g., IPCC, NAS, Wigley and Raper), EPA conducted a study of the probable effects of global warming on sea level rise. As part of a rigorous review process, reviews were sought and received from over 20 prominent members of the domestic and international scientific community. Their views span the range of beliefs on the likely effects of climate change, and of its impact on sea level. A list of these reviewers is attached, many of whom you may be familiar with.

The Agency went a step further and incorporated the reviewers' best estimates of the parameters most important to estimating the extent and probability of sea level rise. Expert opinions were solicited on key factors such as the thermal expansion of the oceans, contributions from Greenland and Antarctica, and the melting of small glaciers. All of the estimates - from skeptics and supporters of global climate change and sea level rise - were used and given equal weight in deriving the results of this study. The reviews also supported the statistical viability and universal acceptance of the quantitative methods used in the study. Drafts of this report were also shared with other

federal agencies, including the Department of Energy, and the U.S. Global Change

In summary, The Probability of Sea Level Rise is an example of EPA's commitment to sound science. I am confident that this study adds substantially to the scientific literature on sea level rise and breaks new ground in making available realistic and useful estimates of the probability of sea level rise to decision-makers, scientists, and the public. Ultimately, this report will help decision makers make batter, more costeffective decisions to protect our coastal areas.

Mr. Chairman, thank you for the opportunity to speak before this Subcommittee. I will be pleased to answer any questions that you may have.

Mr. ROHRABACHER. Thank you very much, Mr. Gardiner. I am tempted to ask what this will do to the shape of the waves and rideability of the surf, but I will not do that. I will wait until later when we get off the record.

But let me ask you this. All of these predictions are projections that you are making here. My staff is telling me that this is not based on computer models. You are not setting this up and putting this into a scenario and working it through in a computer? Is that right?

Mr. GARDINER. I think the description that Mr. Guerrero gave you at the end of the first panel was an accurate description.

What we did, basically, was to take the existing large climate models that were the subject of the first panel. We taken those estimates, including those that the IPCC has used. We then invited in-they give us projections of changes in global temperature.

We then invited in the 20 reviewers that I had mentioned to not only provide comments on what they thought of that, but also to provide additional estimates on other factors that affect sea level rise particularly such as thermal expansion, the rate of melting of Antarctica, Greenland, of other glaciers, those kinds of factors were considered.

We then ran a separate basically computer exercise known as a Monte Carlo exercise to measure probabilities, and the product of that is a curve that looks like, or several curves, actually, that look like the one on that chart there that show a range of probabilities of possible outcomes.

That is not the only one that we came to. That just in our mind seemed to be that is the one that looks at the year 2100 and shows the range of possible outcomes which could occur

Mr. ROHRABACHER. [continuing] —of a catastrophic outcome? Mr. GARDINER. Well, depending on what your definition of "catastrophic" is

Mr. ROHRABACHER. Right. Okay.
Mr. GARDINER. [continuing]

what we show is different prob

abilities for different possible outcomes.

So for an 8-inch sea level rise, we believe there is a very high probability, a 90 percent probability, that that would occur.


Mr. GARDINER. For a larger sea level rise such as an 18-inch— and we believe there is a 50 percent chance that that would occur and we leave it to decision makers to make their own judgments as to which they feel most comfortable with.

Mr. ROHRABACHER. We will go back to that. Thank you very much.

Dr. Moore?


Mr. MOORE. Thank you very much, Mr. Chairman. It is a great honor to be here today to give you my views on this important subject.

As an economist, I have been studying the effects or researching the effects of global warming on humanity. My research has taken two routes.

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