What Will Sea Level Rise Mean For Martha's Vineyard?

Fueled by warming global temperatures, sea level is rising throughout New England. Dukes County, Massachusetts, which is composed of the islands of Martha's Vineyard and Gosnold (South of Cape Cod and West of Nantucket in the map above), could be especially vulnerable to loss of land reclaimed by the sea. How much land is lost, exactly, and damage done will depend on the rate at which the rising occurs and actions taken by policymakers. By looking at data from a couple sources, however, it is possible to begin to understand what elevations of sea level rise could cause damage and which areas could be affected most severely.

First, here are the rates of sea level rise in two locations close to Dukes County- Nantucket and Woods Hole. These NOAA charts show observed trend in sea level during the 20th century:

Both of the charts above show that sea level is indeed rising in the area, but relatively slowly. The Nantucket graph shows a larger increase of 2.95 millimeters a year, but even with this number it would take over 300 years for the sea to rise a full meter. This may seem comforting, but there are still uncertainties within the climate system regarding sea level and recent research has indicated that sea level is rising faster than it has in two thousand years. With factors such as large amounts of ice loss in the polar regions and thermal expansion, this rate could increase. 

So, based on elevation data, let's take a look at what hypothetical increases in sea level would mean for The Vineyard and Gosnold:

While a rise of 1 meter would affect only 1% of the total land area of Dukes County, a rise of 5 meters would be disastrous and leave over 20% of the land in the county inundated. As we can see in the map below, there are large areas that would be vulnerable including much of the southern and eastern coasts of Martha's Vineyard.

An interesting and important conclusion from this analysis is the dramatic increase in effected land if sea level rise were to reach 3 meters. The graph below shows a crucial threshold; an increase of 2 meters will only cumulatively affect about 3% of the county, while the amount of new land affected when sea level rises from 2 to 3 meters is 9% (putting the would-be cumulative total at 12% of the total land in the county).

About this Post: This post includes some of the research I have done as a graduate student here at UConn in the Department of Geography. It was performed using ESRI's ArcMap, Microsoft Excel, and elevation data publicly available from MassGIS. I will be presenting this, in addition to other geographic analyses pertaining to storm surge vulnerability and social vulnerability, in a poster session at the 2012 AAG Annual Meeting in New York City this weekend.

ESRI Map of Carbon Dioxide Emissions

ESRI has produced a map that displays carbon dioxide emissions from 1960 to 2008. The map is dynamic in that it allows the user to pick the year, or consecutive years, to display in addition to having the ability to "play" the map as an animated timeline. Another cool feature of the map is that it has two sets of symbology; the map displays countries' total emissions as a color and relative emissions are represented by dots. For more information, including how the map was made, visit ESRI's Map Story Profile.

Interactive Map Showcases Climatic, Environmental, and Social Research

The Climate Change Adaptation Knowledge and Mitigation Network (AKMN) is "a platform for accessing and sharing current agricultural adaptation and mitigation knowledge". The AKMN website features an ESRI powered map that showcases interdisciplinary research on agricultural and food systems research related to climate change adaptation. In addition to the future implications, the importance of this research can be seen in the present, especially given the current events in Africa. Visit the links above for more!

ArcGIS Tutorial: Creating a Simple Hurricane and Population Map

Last week, I posted a quick map I generated of Irene's path and the population density of the Northeast. I have posted a tutorial on where to find applicable data and how to create something similar in a post on Outside the Neatline.

Irene Heading For Densely Populated Northeast

As of Thursday morning, Hurricane Irene was heading towards the Northeast's population centers.

Communities in the Northeast are preparing for the impact of Hurricane Irene. Mayor Bloomberg is urging citizens to prepare themselves in New York City, and reports are that the city of Boston is investigating potential shelter locations. If Irene comes to shore in the Northeast, there will be large numbers of people affected, which is why some are weary of a potential disaster in the making. Today, I created the population density map above with ArcGIS to show this. On the map, you will find the projected path and cone in addition to population; each dot on the map represents 5,000 people. I have posted a tutorial on where to find the applicable data and how to generate a similar product in ArcMap on Outside the Neatline.

The Rising Sea

In honor of Discovery Channel's Shark Week, the CRE Blog is featuring ocean-related content  this week.

Loss of land-based ice, like on Antarctica, is one of the driving factors behind sea level rise

Climate is the driver of sea level change. The Earth has alternated between Glacial and Interglacial Periods for millions of years. During a Glacial Period, or Ice Age, much of the water on Earth is trapped in ice sheets and, consequently, sea level drops. Interglacial Periods, on the other hand, are times of warmer temperatures which cause ice sheets to melt. When the ice becomes liquid water, it eventually finds its way to the oceans and raises the sea level. In addition, because the oceans are warmer during interglacial periods, the water expands (known as thermal expansion), which also adds to the sea level rising.

This animation from NOAA shows evidence of loss of ice in the North Pole.

Sea level has steadily risen 1-2.5 millimeters a year since 1900, and it is expected to continue to rise throughout the 21st century. Although there is no perfect model to absolutely predict the future, it is possible to investigate "What If?"

Models based on elevation data can predict what areas could be vulnerable due to rising sea levels.

The Department of Geosciences Environmental Studies Laboratory at the University of Arizona has a web tool that does just that. They have developed a Geographic Information System (GIS) that uses Digital Elevation Models (DEM) to show what areas are potentially vulnerable to sea level change. This web visualization, developed with ESRI's ArcViewer for Flex, allows users to set the amount of sea level rise in one meter increments with a range from no change to six meters.