NASA’s Water-observing Satellite Sends First Images back to Earth

A recently launched satellite designed to study all water across the world has begun sending its first images back to Earth.

The American space agency NASA says the satellite is expected to measure the elevation¹ of nearly all water on Earth's surface. It is the largest and most detailed² effort yet to map the world's water.

The satellite is called SWOT, which stands for Surface Water and Ocean Topography. SWOT is a joint³ project between NASA and the French space agency, CNES.

The satellite uses radar⁴ technology and other instruments to collect detailed height and surface measurements of water in oceans, lakes and rivers. Oceans cover more than 70 percent of Earth's surface.

Researchers say the information can help them learn more about how the world's water supply influences climate change.

One major goal of the project is to research how oceans take in atmospheric⁵ heat and carbon dioxide. The natural process moderates temperatures and climate change.

Data will be recorded from radar readings on about 90 percent of Earth's surface. Such data can support efforts to learn about ocean currents, predict the weather and control freshwater supplies in areas with little rain, NASA says.

The information is also expected to assist communities as they seek to improve and manage their water resources and prepare for floods and other disasters, the researchers said.

NASA Administrator⁶ Bill Nelson spoke⁷ about SWOT's activities as the first observations of the world's water supply arrived to Earth.

"SWOT's advanced imagery will empower researchers and advance the way we manage fresh water and the effects of sea level rise" across the world, Nelson said in a statement. He added that water is one of the planet's most important resources and is threatened by elements of climate change.

"SWOT will provide critical information that communities can use to prepare for the impacts of a warming climate," Nelson added.

The images use colors to identify elevation levels in different bodies of water. In one example of its first work, SWOT measured sea levels off the coast of North Carolina and Virginia. A radar instrument on the satellite collected data on an ocean area about 120 kilometers across.

NASA said red and orange areas in the images represented sea levels that were higher than the worldwide average. On the other hand, areas shown in blue represented sea levels that were lower than average.

The research team involved in the project said SWOT provides big improvements over measurements captured by other space-based instruments called altimeters. Those instruments are only able to look at a narrow area of Earth directly beneath them. But NASA says SWOT's instruments are designed to observe sea levels across much wider areas.

SWOT's radar instrument can also collect data through clouds and darkness. This will permit scientists to map observations under different weather conditions and cover large areas at any time of day.

Philippe Baptiste is the chairman and chief executive of CNES. He said in a statement, "Our ability to measure freshwater resources on a global scale through satellite data is of prime importance as we seek to adjust to a changing climate."

He added: "The first views from SWOT give us a clearer picture than ever before. These data will prove highly valuable for the international community in the fields of hydrology, oceanography, and coastal⁸ studies."

Parag Vaze is a SWOT project manager at NASA's Jet Propulsion Laboratory in California. He said he hopes researchers, policymakers and water resource managers around the world will examine the data collected by SWOT.

"(The satellite) took years to develop and build," Vaze said, "and it will collect information on bodies of water across the globe – data that will be freely and openly available to everybody who needs it."

Words in This Story

elevation – n. the height of a place above sea level

manage – v. to do something or deal with something successfully

advanced – adj. having developed or progressed to a late stage

impact – n. the effect a person, event or situation has on someone or something

prime – adj. main or most important

adjust – v. to change something slightly to get it to work better

hydrology – n. the study of Earth's water supply

1 elevation   

n.高度；海拔；高地；上升；提高

参考例句：

• The house is at an elevation of 2,000 metres.那幢房子位于海拔两千米的高处。
• His elevation to the position of General Manager was announced yesterday.昨天宣布他晋升总经理职位。

2 detailed   

adj.详细的，详尽的，极注意细节的，完全的

参考例句：

• He had made a detailed study of the terrain.他对地形作了缜密的研究。
• A detailed list of our publications is available on request.我们的出版物有一份详细的目录备索。

3 joint   

adj.联合的，共同的；n.关节，接合处；v.连接，贴合

参考例句：

• I had a bad fall,which put my shoulder out of joint.我重重地摔了一跤，肩膀脫臼了。
• We wrote a letter in joint names.我们联名写了封信。

4 radar   

n.雷达，无线电探测器

参考例句：

• They are following the flight of an aircraft by radar.他们正在用雷达追踪一架飞机的飞行。
• Enemy ships were detected on the radar.敌舰的影像已显现在雷达上。

5 atmospheric   

adj.大气的，空气的；大气层的；大气所引起的

参考例句：

• Sea surface temperatures and atmospheric circulation are strongly coupled.海洋表面温度与大气环流是密切相关的。
• Clouds return radiant energy to the surface primarily via the atmospheric window.云主要通过大气窗区向地表辐射能量。

6 administrator   

n.经营管理者，行政官员

参考例句：

• The role of administrator absorbed much of Ben's energy.行政职务耗掉本很多精力。
• He has proved himself capable as administrator.他表现出管理才能。

7 spoke   

n.（车轮的）辐条；轮辐；破坏某人的计划；阻挠某人的行动 v.讲，谈（speak的过去式）；说；演说；从某种观点来说

参考例句：

• They sourced the spoke nuts from our company.他们的轮辐螺帽是从我们公司获得的。
• The spokes of a wheel are the bars that connect the outer ring to the centre.辐条是轮子上连接外圈与中心的条棒。

8 coastal   

adj.海岸的，沿海的，沿岸的

参考例句：

• The ocean waves are slowly eating away the coastal rocks.大海的波浪慢慢地侵蚀着岸边的岩石。
• This country will fortify the coastal areas.该国将加强沿海地区的防御。