Introduction

Aug. 23, 2015, marks the 10-year anniversary of Hurricane Katrina, a Category 5 hurricane which produced wind speeds over 274 kilometers per hour (170 miles per hour) and caused severe destruction from Florida to Louisiana. The storm that would become Katrina formed over the Bahamas on Aug. 23, 2005, and reached hurricane status two days later as it passed over southern Florida. Katrina made landfall over Mississippi and Louisiana on the morning of Aug. 29, 2005, as a Category 3 Hurricane, which means it was producing winds speeds of 178 to 209 kilometers per hour (approximately 111 to 129 miles per hour). According to the National Hurricane Center, the massive storm caused severe destruction throughout the area totaling $108-billion in damage. To date, Katrina is the most expensive hurricane in United States history.

Science Objectives

Hurricane Katrina caused environmental changes in the shape, elevation, and even locations of islands and wetlands, as well as the loss of sand, sediment, and vegetation. Scientists can use satellite imagery to better understand the impact hurricanes have on ecological areas by using various types of satellite data to detect changes the area has experienced. The Terra platform's Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor is especially useful for this kind of research due to its ability to capture specific areas at defined points in time.

Major Findings

The ASTER images below illustrate some of the damage inflicted on the Chandeleur Barrier Islands, located east of the Mississippi Delta, in the aftermath of Hurricane Katrina. The Chandeleur Barrier Islands act as a natural layer of protection for the Chandeleur Sound and Biloxi marsh, assisting in limiting the impact of ocean waves, storm surges, and salinity intrusion that can harm inner wetlands and the mainland. As part of the Breton National Wildlife Refuge, these islands are identified as a critical habitat for wildlife and are a very important stop for many birds migrating between North and South America. Winds and storm surge from Hurricane Katrina washed out the once 40 kilometer (24.8 mile) long dunes, and left pockets of marsh fragments in its wake. According to Sallenger and others (2009), a total of 82% of the islands’ surface area was lost due to Hurricane Katrina. The height of the islands was reduced from five meters (16.4 feet) to less than a half meter (1.6 feet). According to the USGS, if barrier islands were to disappear it could increase the rate of deterioration of the wetlands the islands are currently protecting.

References

Article References

Dreher, C., Flocks, J., and Lavoie, D., 2007, Assessing the resilience of a vital barrier-island chain – Chandeleur and Breton Islands, Louisiana, accessed August 5, 2015, at http://soundwaves.usgs.gov/2007/12/fieldwork2.html.

Government Publishing Office, 2006, The impact of Hurricanes Katrina and Rita on the National Wildlife Refuge System oversite hearing, accessed August 5, 2015, at gpo.gov/fdsys/pkg/CHRG-109hhrg26654/html/CHRG-109hhrg26654.htm.

List, J., Louisiana Barrier Islands: A Vanishing Resource, accessed August 19, 2015.

National Climatic Data Center, 2005, Hurricane Katrina, accessed August 19, 2015, at http://www.ncdc.noaa.gov/extremeevents/specialreports/Hurricane-Katrina… (link removed by source).

National Geographic, 2010, Hurricane Katrina: The essential time line, accessed July 16, 2015, at http://news.nationalgeographic.com/news/2005/09/0914_050914_katrina_tim… (link removed by source).

National Hurricane Center, 2011, The deadliest, costliest, and most intense United States tropical cyclones from 1851 to 2010 (and other frequently request hurricane facts), accessed August 11, 2015 at nhc.noaa.gov/pdf/nws-nhc-6.pdf.

National Weather Service Natural Hurricane Center, Saffir-Simpson hurricane wind scale, accessed July 16, 2015.

National Wildlife Federation, 2006, When hurricanes hit habitat, accessed July 27, 2015.

Sallenger, A., Wright, C., Howd, P., Doran, K., and Guy, K., 2009, Extreme coastal changes on the Chandeleur Islands, Louisiana, during and after Hurricane Katrina, accessed August 5, 2015, at pubs.usgs.gov/sir/2009/5252/downloads/Chapter-B/Chapter-B.pdf.

Tibbetts, John, 2006, Louisiana’s wetlands— A lesson in nature appreciation: Environmental Health Perspectives, v. 114, no 1, p. A40–A43, at ncbi.nlm.nih.gov/pmc/articles/PMC1332684/.

U.S. Fish & Wildlife Service, 2013, Breton National Wildlife Refuge, accessed July 27, 2015, at http://www.fws.gov/breton/ (link removed by source).

Image References 

Aug. 29, 2005, MODIS Surface Reflectance Mosaic Image Granule IDs

• MYD09GA.A2005241.h09v05.005.2008061055945
• MYD09GA.A2005241.h09v06.005.2008061062850
• MYD09GA.A2005241.h10v05.005.2008061055410
• MYD09GA.A2005241.h10v06.005.2008061060023
• MYD09GA.A2005241.h11v05.005.2008061055518
• MYD09GA.A2005241.h11v06.005.2008061063227
• MOD09GA.A2005241.h11v06.005.2008061004050
• MOD09GA.A2005241.h10v06.005.2008061002650

2005-2015 Infrared False-Color AST_L1B Images Granule IDs

• AST_L1B_00308072005164249_20101107022539_8121
• AST_L1B_00309082005164230_20101105183828_23951
• AST_L1B_00308212010164312_20100827202729_5260
• AST_L1B_00307182015164444_20150720124649_24803