Posts Tagged ‘oceans’

In a State of Flux

Thursday, September 1st, 2011

By Amber Jenkins

This post was written for My Big Fat Planet, a blog hosted by Amber Jenkins on NASA’s Global Climate Change site.

Latest Image of Vesta captured by Dawn on July 17, 2011
COLD SNAP: Petermann Glacier, Greenland. Left: June 26, 2010. Right: August 13, 2010. An iceberg more than four times the size of Manhattan broke off the Petermann Glacier (the curved, nearly vertical stripe stretching up from the bottom right of the images) along the northwestern coast of Greenland. Warmer water below the floating ice and at the sea’s surface were probably responsible for the break.
› See more images of our changing Earth from State of Flux

They say a picture says a thousand words. This week we published our 100th image in State of Flux, our gallery showing images of change around our planet. So hopefully by now you’re in awe of our home planet and the ways in which it is constantly changing, and aware of the impact us humans can have.

Each week for the past couple of years, we’ve published new images of different locations on planet Earth, showing change over time periods ranging from centuries to days. The pictures have been taken from space, by NASA’s Eyes on the Earth (its fleet of satellites whizzing above our heads), and from the ground, by real-life people. Some of the changes seen are related to, or exacerbated by, climate change, and some are not. Some document the effects of urbanization and man’s impact on the land, while others the ravage of disasters such as fires and floods.

Seeing our planet from space gives us a global view that we can’t get elsewhere. Through those eyes, we’ve witnessed damage caused by the recent tsunami in Japan, glacier melt in the Himalayas, the greening of China, the growth of Las Vegas and a century of global warming. We’ve looked at the march of deforestation in Bolivia, the rumblings of the (unpronounceable) Icelandic volcano Eyjafjallajökull, and the damming of the River Nile. Take a look below at some of our favorites. Sign up to our monthly newsletter or subscribe to our Facebook page if you want to keep up to date with our latest images. We’ll be launching a brand spanking new version of the gallery soon!

See more of some of the most stunning images from State of Flux on My Big Fat Planet.


Oceans Up Close - From Space

Thursday, April 2nd, 2009
Jorge Vazquez
by Jorge Vazquez
Oceanographer

Not all oceanographers spend their time out on the seas. As a project scientist for the Physical Oceanography Distributed Active Archive Center here at JPL , I study the world’s ocean from my computer, using data from a series of NASA satellites that orbit Earth. These data measure everything from how the ocean changes during an El Nino to how such climatic changes affect local regions like California’s coast.

This kind of precise data was impossible 100 years ago. In fact, scientific and technological advances over the last century have revolutionized the field of oceanography. Today, we gather data both from instruments in the ocean and from satellites in space. These satellite data measure changes in sea surface topography (the ocean surface has changes in elevation, just like the land), ocean surface winds, sea surface temperature and water pressure at the bottom of the ocean. The satellites view the ocean from 700 to 1,300 kilometers (440 to 800 miles) above Earth. Current advanced technologies allow scientists to combine data from different satellites to view ocean conditions in near-real time, only 6 to 12 hours from when the satellite acquires the data. This information can then be sent to researchers and decision makers for use in improving forecasts for hurricanes to the regional and local impacts of ocean phenomena like El Nino and La Nina.

The image shows temperatures off the coast of California in September of 1997 (El Nino).
Image above: Sea surface temperatures in 1997 during El Nino and in 2008, when the waters had returned to more normal conditions.Image credit: NOAA

Examples of satellite data can be seen in these images. The view on the left shows temperatures off the coast of California in September of 1997 (El Nino). On the right, sea surface temperatures from September of 2008 (normal conditions). Notice the warmer temperatures (seen in red) resulting from the 1997-1998 El Nino event. Such temperature changes have direct impacts on local climate and fisheries. These data are leading to a new understanding of how hurricanes get their energy from the ocean. These satellite data also help forecast regional ocean temperatures, which affect local weather.

As technology improves, along with the availability of these data in real time, new opportunities will continue to expand to better understand our planet and its impacts on our lives.