By Stephanie Nebehay
GENEVA (Reuters) - The United Nations' weather agency will ask NASA and other space agencies next week to make their next generation of satellites available to monitor climate change, a senior official at the U.N. body said on Friday.
The aim is to ensure that satellites launched over the next 20 years constantly record parameters such as sea levels and greenhouse gases in the atmosphere, the World Meteorological Organization (WMO) said.
"The main focus of the meeting next week will be the expansion of the global observing system by satellites to not only monitor severe weather, which is a core function, but also to monitor climate on a very continuous and long-term basis," WMO expert Jerome Lafeuille told a news briefing in Geneva.
Senior officials from NASA, the European Space Agency, and space agencies in Japan, China, Brazil and India are due to attend the WMO meeting in New Orleans from Jan 15-16.
Satellites are an essential part of efforts to track severe weather and climate change by providing a global picture of shifts in the climate system, rising ocean levels, impacts on land and in the atmosphere, says the WMO.
Scientists blame climate change mainly on human emissions of greenhouse gases from burning fossil fuels and warn it will bring extreme weather including more heatwaves, droughts, floods and rising seas.
At least 16 geostationary and low-earth orbit satellites currently provide operational data on the planet's climate and weather as part of WMO's global observation system.
There are also numerous experimental satellites designed for scientific missions or instrument technology demonstration -- measuring variables such as wind, precipitation and temperature -- whose data WMO wants to ensure is captured long-term.
"We know there are gaps. Climate monitoring needs very long-term continuity of measurement," Lafeuille, who heads the space-based observing system division of WMO's space program, told Reuters.
"When you look at satellites programmed over the next two decades there are a number of extremely useful satellites but there is no guarantee of continuity of key measurements."
High on WMO's agenda will be ensuring constant monitoring of sea levels for several decades, said the French expert.
Measuring the chemical make-up of the atmosphere -- including greenhouse gases such as CO2 as well as aerosols -- is also key, Lafeuille said.
A record number of 17 satellites are planned for launch in 2008 by countries from China to India and Russia, he said. "Our challenge at WMO is to make sure programs are complementary and that all together we build an optimized system."