Permanent Service for Mean Sea Level. Data from around the world, and linear regression coefficients that provide a trend. Before drawing conclusions about a location, make sure that the site has more than 40 years, or that there is a nearby site corroborating the trend.

National Ocean Service: Sea Levels Online. If you want to know about the United States, this new site may be more useful than the Permanent Service—especially because of how it is integrated into related information from NOAA.

Map summarizing worldwide sea level trends.

Intergovernmental Panel on Climate Change: Science of Climate Change. This is the "party line" estimate of global warming and sea level rise by the year 2100. Caution: The analysis was not designed for coastal planning purposes but rather to indicate consequences of greenhouse gases.

US Comments on IPCC. IPCC’s projections failed to include all of the possible contributions from Antarctica. In addition, the report should have provided results in a format more amenable to making local projections and reconciled model-data inconsistencies. Example: all IPCC models project acceleration of sea level rise, but the low projection is less than the historic trend. How can that be? (Note: Department of State pulled these comments off their web page--I'll try to post when I can find them).

The Probability of Sea Level Rise. This is the first probabilistic assessment of global warming and sea level rise from greenhouse gases. This report was designed for coastal planning. Therefore it includes a chapter on local projections that reconciles the models with data. Unlike IPCC, all scenarios based on models that project acceleration show the sea rising more rapidly in the future than the past. The probabilities provide useful "worst-case" scenarios, and also quantify "worse-case" scenarios with 5 and 10% probabilities.

The most recent paper on the subject by Tom Wigley. During the 1990s, his models were the backbone of the IPCC science assessments. He still is often ahead of the curve. A reasonable practitioner will always find out how his projections compare with the most recent IPCC assessment. He usually reports results in a fashion that allows ready comparison. The Captain uses his analysis to consider the most likely rise in sea level, but not the worse-case or worst-case scenario. See his 2002 explanation

The most recent paper on the subject by Jim Hansen. The Captain’s candidate for the next Nobel Prize awarded for climate change research. Although he helped EPA get started in assessing the consequences of sea level rise in 1983, he moved on to other issues. But twenty years later he came back to this issue, with a provocative essay in Climatic Change warning that greenhouse gases may put polar glaciers on a "slippery slope to Hell." The Captain uses these analyses to consider worse-case scenarios. (This looks like an impermanent link so if it moves, search for "slippery slope", James Hansen, and "sea level rise". )

Have we Overstated or Oversimplied the Problem?

The Greening Earth Society's summary of why most of what EPA and IPCC have written is probably wrong. Most of this article is useful background, articulated in a thoughtful way. It includes a few cheap shots about other people's views, but given the publisher's clearly stated mission, the article probably wouldn't have been published without a few jabs at EPA and IPCC. Too bad the authors did not contact me:  I could have given them citations of foolish things that really happenned!

EPA's mea culpa for having over-estimated future sea level rise during the 1980s. Included in Chapter 8 of the Probability of Sea Level Rise.  Text-only version.

The Sky Isn't Falling and the Sea Isn't Rising. A Classic by Fred Singer.

Don't Cry for Them: The Maldives' Islands are OK. Nils-Axel Mörner and Michael Tooley team up to challenge the view that sea level is rising relative to this atoll nation. Too bad the British didn't intall a tide guage when they established the naval base at Gan. See also the peer-reviewed paper.  For another view, see 1989 paper recommending that the Maldives should elevate their populated islands and a speech about sea level rise to the United Nations by President Gayoom.  (As of January 1, 2005, the title of the paper now seems unfortunate.  One option for tsunami relief is Friends of Maldives.

Published Benchmark Sheets. My deck hands won’t even go to this site until I’ve asked them thrice. But my engineer understands that (with the exceptin of some unpublished EPA maps) the elevations you see on most maps are not relative to sea level. For example, the 5-foot contour is not 5 feet above sea level; it is 5 feet above a "benchmark", such as National Geodetic Vertical Datum of 1929, or the North Atlantic Vertical Datum of 1988. How high is sea level compared to the benchmark? Go to this site and find out.
The Captain recommends that you always consider how high the land is relative to mean spring high water (the average full moon tide)

Topozone. Virtually all of the USGS 1:24,000 maps are available for checking our elevations. You are of course subject to the limitations of the contour interval USGS used. For sea level rise purposes, I stick to the Atlantic Coast from Connecticut South, and the Gulf of Mexico. The 1:100,000 and 1:250,000 maps are good for getting your bearing. You are limited to the contours USGS used, which occasionally makes no sense (e.g. 20-foot contours in Kent Island, Maryland and Horry County, South Carolina).

Terraserver: This site has the same maps as Topozone, but gives you less control over which map-scale you are examining when you alter the screen scale. On the other hand, it does have aerial photographs.

Statewide Elevation maps from EPA. These maps give one a sense of nationwide vulnerability. If you have an 11 X 17 printer, I recommend the map that has the entire eastern half of the United States. But the maps only have 1.5- and 3.5-meter contours, and elevations are relative to the National Geodetic Vertical Datum, not sea level. EPA is attempting to remedy this situation in its next generation of maps.

General

Sea Level Rise Reports

More Sea Level Rise Reports

Captain Sea Level's Christmas Song: When the North Pole Melts