NASA to run first global water survey from space

Mission will conduct a comprehensive survey that aims to shed new light on mechanics and consequences of climate change.

A NASA-led international satellite mission is set to take off from Southern California this week to conduct a comprehensive survey of the world’s oceans, lakes and rivers for the first time.

A major Earth science project will use an advanced radar satellite known as the Surface Water and Ocean Topograph (SWOT) which is designed to give scientists an unprecedented view of the life-giving fluid covering 70 percent of the planet to shed new light on the mechanics and consequences of climate change.

A Falcon 9 rocket, owned and operated by commercial launch company SpaceX owned by the billionaire Elon Musk is set to take off before dawn on Thursday from the Vandenberg Space Force Base, about 275 km (170 miles) northwest of Los Angeles, to carry SWOT into orbit.

If the mission goes according to plan, the satellite should produce research data within several months.

It took nearly 20 years to develop SWOT, which incorporates advanced microwave radar technology. According to scientists, it should collect height-surface measurements of oceans, lakes, reservoirs and rivers in high-definition detail across 90 percent of the globe.

The data, compiled from radar sweeps of the planet at least twice every 21 days, will enhance ocean-circulation models, bolster weather and climate forecasts, and aid in managing scarce freshwater supplies in drought-stricken regions, according to researchers.

One of the main aims of the mission is to analyse how oceans absorb atmospheric heat and carbon dioxide in a natural process that moderates global temperatures and climate change.

The satellite is designed to precisely measure fine differences in surface elevations around smaller currents and eddies, where much of the oceans’ drawdown of heat and carbon is believed to occur. And SWOT can do so with 10 times greater resolution than existing technologies, according to NASA’s Jet Propulsion Laboratory, which designed and built the satellite.

“It’s really the first mission to observe nearly all water on the planet’s surface,” said JPL scientist Ben Hamlington, who also leads NASA’s sea-level change team.

Studying the mechanism by which that happens will help climate scientists answer a key question: “What is the turning point at which oceans start releasing, rather than absorbing, huge amounts of heat back into the atmosphere and accelerate global warming, rather than limiting it,” said Nadya Vinogradova Shiffer, SWOT’s programme scientist at NASA in Washington.

Freshwater bodies are another key focus for SWOT, equipped to observe the entire length of nearly all rivers wider than 100 metres (330 feet), as well as more than one million lakes and reservoirs larger than 62,500 square metres (15 acres).

Taking inventory of Earth’s water resources repeatedly over SWOT’s three-year mission will enable researchers to better trace fluctuations in the planet’s rivers and lakes during seasonal changes and significant weather events.

NASA’s SWOT freshwater science lead, Tamlin Pavelsky, said collecting such data was akin to “taking the pulse of the world’s water system, so we’ll be able to see when it’s racing and we’ll be able to see when it’s slow”.

Source: News Agencies