Saturday, August 14, 2010

Space Solutions Proposed To Lessen Africa's Vulnerability To Natural Disasters

From: Spacemart

Africa faces a mounting number of disasters, such as floods, drought, food security and the spread of diseases, but must also deal with the likely impact of global climate change that could intensify these problems.

To help tackle these tragic threats to Africa's human and economic well-being, space-based technologies are being identified.

Nearly a 100 decision-makers and senior experts on disaster-risk management from African countries, Europe, the Middle East and America met July 6-9 in Addis Ababa, Ethiopia.

The burning area shifts from north to south over the course of the year, in step with the coming and going of Africa's rainy and dry seasons Although fires are a part of the natural cycle of the seasonally dry grasslands and savannas of Africa, ecologists, climatologists, and public health officials still have reasons to be concerned about Africa's intense burning. This series of images shows the seasonal fire patterns in Africa throughout 2005. The images are based on fires detected by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra and Aqua satellites. NASA images courtesy the MODIS Rapid Response Team, Goddard Space Flight Center.  

This notable gathering of officials was organized by the United Nations Platform for Space-based Information for Disaster Management and Emergency Response, known as UN-SPIDER together with the United Nations Economic Commission for Africa (ECA) with support of the Government of Austria and in cooperation with Secure World Foundation.

The UN ECA called for more use of space-based technologies in Africa.

Disasters do not discriminate
In addressing the group, Agnieszka Lukaszczyk, space policy consultant for Secure World Foundation (SWF), also actively participated in the four-day meeting titled: "Building upon Regional Space-based Solutions for Disaster Management and Emergency Response for Africa."

This event was held as a regional workshop of the UN-SPIDER.

The workshop focused on involving Africa more actively and promoting access for African countries to the use of space-based applications and solutions targeting disaster-risk management, emergency response, and climate change and health-related issues.

SWF's Lukaszczyk addressed the participants and commented that the Foundation is committed to supporting efforts that lead to sustainable development through the use of space applications.

"Modern societies already benefit from services provided by satellites including telecommunications and navigation," Lukaszczyk said. "It is fact that disasters do not discriminate and do not follow political boundaries among countries. There is need to promote cooperation as a cornerstone to promote development."

The Addis Ababa workshop brought together authorities on disaster-risk management, drawing upon the expertise from space agencies, remote sensing and mapping agencies responsible for providing space-based technologies and solutions for disaster management support.

Thursday, August 12, 2010

Floating Ice Contributes to Rising Sea Levels


Analysis by Zahra Hirji  (From: DiscoveryNews)

Over the last century, global sea level rose by more than half a foot. The predictions about how much the seas will swell in the next century are much worse, with some models forecasting that the arctic will be entirely ice-less and that ocean levels will increase by a meter or more.

Now a new study suggests that these already staggering predictions may, in fact, be too low because they do not account for the contribution of melt from floating ice.

Until now, climatologists have treated the melting of floating ice like the melting of ice cubes in a cup of water. When an ice cube melts, the water in the cup does not overflow because the total volume of water before and after the melting occurred remains the same.

But in the case of icebergs and the ocean, researcher Andrew Shepard from the University of Leeds in London proved that it is not the same. The composition of icebergs differs substantially from the ocean water they live in. Icebergs have a high amount of fresh water, which is less dense than the surrounding heavy salt water.

When a piece of iceberg melts, fresh water floats on top of salty, rather than mixing together. The layering results in a slight volume increase. 

Using satellite data and an ice-ocean computer model, Andrew Shepherd of the University of Leeds and his colleagues tracked the changes in floating ice volume around the world between 1994 and 2004. The ice produced enough melt to raise the oceans .049 millimeters per year, according to the team's article in the journal Geophysical Research Letters.

In comparison to the 1.6 millimeters per year added to the ocean as it warms, or the .8 millimeters per year coming from land-based glacier and melting ice sheets, the impact of floating ice is very small.

Over time, however, the amount adds up. Shepard estimates that if all the ice floating around the ocean melted, global sea levels would increase 1-2 inches. On a regional level, melting could be much greater.

An article in Scientific American reported that a one meter increase in global sea level would result in the loss of 861,000 square miles of land, affecting 145 million people.

As Shepherd argues in his study, it is crucial that sea level rise models start including the contribution of floating ice melt. Knowing exactly what sources are contributing to sea level rise and by how much is essential for protecting the string of vulnerable communities situated along the world's coastlines, from New York City to Bombay.