Climate of Our Future

NASA Satellites Eye Coastal Water Quality

Science Daily — Using data from instruments aboard NASA satellites, Zhiqiang Chen and colleagues at the University of South Florida in St. Petersburg, found that they can monitor water quality almost daily, rather than monthly.

High concentrations of microscopic plants called phytoplankton (red regions) along the Florida coast and in Tampa Bay are an indicator of ocean health and change as seen in this SeaWiFS image from October 2004. Researchers have successfully used data from similar images to monitor almost daily changes in coastal water quality. (Credit: SeaWiFS Project)

Such information has direct application for resource managers devising restoration plans for coastal water ecosystems and federal and state regulators in charge of defining water quality standards.The team’s findings, published July 30 in two papers in Remote Sensing of Environment, will help tease out factors that drive changes in coastal water quality. For example, sediments entering the water as a result of coastal development or pollution can cause changes in water turbidity — a measure of the amount of particles suspended in the water. Sediments suspended from the bottom by strong winds or tides may also cause such changes. Knowing where the sediments come from is critical to managers because turbidity cuts off light to the bottom, thwarting the natural growth of plants. Read More

Greece Suffers More Fires In 2007 Than In Last Decade, Satellites Reveal

Science Daily — Greece has experienced more wildfire activity this August than other European countries have over the last decade, according to data from ESA satellites. The country is currently battling an outbreak of blazes, which began last Thursday, that have spread across the country killing more than 60 people.

Number of fires occurring monthly for France, Italy, Spain, Portugal and Greece from July 1996 to August 2007. These data are based on results from the Along Track Scanning Radiometer (ATSR) on ESA’s ERS-2 satellite, launched in 1995, and the Advanced Along Track Scanning Radiometer (AATSR) on ESA’s Envisat satellite, launched in 2002. These twin radiometer sensors work like thermometers in the sky, measuring thermal infrared radiation to take the temperature of Earth’s land surfaces. Temperatures exceeding 308º K at night are classed as burning fires. (Credit: ESA)

ESA’s ERS-2 and Envisat satellites continuously survey fires burning across the Earth’s surface with onboard sensors – the Along Track Scanning Radiometer (ATSR) and the Advanced Along Track Scanning Radiometer (AATSR) respectively, known as the ATSR Word Fire Atlas, which is available to users online in near-real time.

The ATSR World Fire Atlas is the longest worldwide fire atlas available. Even if the atlas is not supposed to pick up all fires due to satellite overpass constraints and cloud coverage, it is statistically representative from one month to the other and from one year to the other. Read More