People of Manhattan at Risk

Introduction

Global sea levels have been rising slowly for the past hundred years or so. This poses a significant danger to the more than one billion people worldwide living in the coastal zone (Nicholls et al. 2007). Coastal areas are already vulnerable to storms and other catastrophic events, as was powerfully demonstrated when Hurricane Katrina devastated New Orleans and other Gulf Coast cities in 2005 and when a tsunami razed much of northeastern Japan in March 2011.

One densely populated and globally important city in the coastal zone is New York City. On September 11, 2001, this city experienced an otherwise unimaginable loss of life and property in the attack on the World Trade Center.

With rising sea levels and projected increases in the number and magnitude of storms and storm surges, it's reasonable to wonder:

How many people in Manhattan are currently at risk from flooding by a major hurricane?

How many people in Manhattan could rising sea level displace by 2100?

Location

Manhattan or New York County, New York, USA

Time to complete the lab

45 minutes

Prerequisites

Advanced GIS experience

Data used in this lab

Three Esri grids called flood_bcs (best-case scenario for sea level rise), flood_storm (sea level rise due to a hurricane), and flood_wcs (worst-case scenario for sea level rise) and a shapefile called manh_pop, which includes population numbers for 2000 and 2100 by census tract

Census tract data for New York in projection Latitude/Longitude, 1927 datum at http://www.census.gov/geo/www/cob/tr2000.html

Census2000.xlsx (See http://www.census.gov/ or http://factfinder2.census.gov/)

US Geological Survey national map server at http://cumulus.cr.usgs.gov/webappcontent/neddownloadtool/NEDDownloadToolDMS.html

The provided file manh_outline (the boundary for the county of New York), originally downloaded from the US Census Bureau at http://www.census.gov/geo/www/cob/co2000.html; file then projected to universal transverse Mercator (UTM) NAD 1983 Zone 18N and clipped to New York County (FIPS = '061')