NASA’s flying observatory watches Earth’s clouds 

Posted: December 20, 2015 by oldbrew in atmosphere, Clouds, research
Tags:

DSCOVR observatory [image credit: NASA]

DSCOVR observatory [image credit: NASA]


Solid data on global cloud cover seems hard to come by, but NASA’s Deep Space Climate Observatory (DSCOVR) could be changing that. SpaceRef reports.

From a dusty atmosphere stretching across the Atlantic Ocean to daily views of clouds at sunrise, a new NASA camera keeping a steady eye on the sunlit side of Earth is yielding new insights about our changing planet.

With NASA’s Earth Polychromatic Imaging Camera (EPIC), affixed to NOAA’s Deep Space Climate Observatory (DSCOVR) about one million miles from Earth, scientists are getting a new view of our planet’s clouds, land surfaces, aerosols and more.


Science results from the first EPIC images were discussed Monday at a media briefing at the American Geophysical Union meeting in San Francisco.

EPIC captures a color image of the sunlit side of Earth at least once every two hours, allowing researchers to track features as the planet rotates in the instrument’s field of view. “With EPIC, you see cloud structure from sunrise on the left to sunset on the right,” said Jay Herman, EPIC instrument lead investigator at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and the University of Maryland, Baltimore County. “It’s the only view we have like this where everything is at the exact same instant in time, even though the local times are different.”

EPIC takes measurements in visible, ultraviolet and near-infrared wavelengths. With the ultraviolet channels, Herman can watch as dust from the Sahara travels westward across the Atlantic. While other low-Earth orbit satellite instruments can pick this up as they orbit at a fixed local time, EPIC provides a day-long view of the process.

“We can see the progression in real time, as it flows across the Atlantic,” Herman said.

Researchers also can determine the height and location of daytime clouds by comparing EPIC images at two different wavelengths. This measurement is important in calculating Earth’s energy balance for climate studies, as well as for tracking weather. For example, hurricanes show up as a high spiral of clouds surrounding a clearly visible eye.

“Because of the unique location and field of view, every day brings something new and unexpected,” said Alexander Marshak, DSCOVR deputy project scientist at Goddard.

One example Marshak points out is that, even a million miles away, EPIC can see the tracks of ships crossing the ocean. Some of the first images from EPIC show the clouds that result from the ships’ smoke plumes.

Researchers also are analyzing EPIC data to better understand vegetation, aerosols, ozone and other features of Earth and its atmosphere.

DSCOVR was launched on Feb. 11 and, after a four-month journey, reached its orbit around the first Lagrange point, where the matching pull of gravity from the sun and Earth allows the satellite to stay relatively stable between the two bodies. The satellite, a joint mission between NOAA, NASA and the U.S. Air Force, also carries instruments facing the sun that will the study solar wind and its magnetic field.

A second NASA Earth-facing instrument on DSCOVR, the National Institute of Standards and Technology Advanced Radiometer (NISTAR), measures the total amount of solar energy that reflects off Earth, as well as the heat emitted from our planet, according to Steven Lorentz, NISTAR instrument lead investigator and president of L-1 Standards and Technology, Inc. Because of this, the instrument fills in a missing piece of energy information not observed by other satellites.

Even with less than a year’s worth of data, the energy reflected off Earth is showing patterns, he said. The instrument picks up fluctuations, with more light reflected from continents and clouds than from oceans.

“Whenever Africa is in view, we get the highest photo-reflectance,” Lorentz said. “And, even though it’s the same planet spinning, the amount of cloudiness varies planet-wide every day.”

Earth’s reflectiveness varies throughout the year, as well. As Antarctica tilts towards the sun in November, NISTAR’s signal edges up as the massive ice sheet changes the planet’s energy budget. It’s a measurement that, over time, could help scientists studying how the reflectance of the sun’s energy back into space can impact Earth’s changing climate.

Source: EPIC Instrument on DSCOVR Watches Earth’s Clouds – SpaceRef

For more information on EPIC, and to view images captured by the instrument, visit: http://epic.gsfc.nasa.gov/

Comments
  1. oldbrew says:

    The image appears at NASA’s ‘DSCOVR at a Glance’ info graphic (tech. details) here:
    http://www.nesdis.noaa.gov/DSCOVR/spacecraft.html

  2. Richard111 says:

    A heartening read. Thanks for this. Hope we learn more before it gets shut down.

  3. oldbrew says:

    More and/or better cloud cover data is important.

    ‘Clouds play multiple critical roles in the climate system. In particular, being bright objects in the visible part of the solar spectrum, they efficiently reflect light to space and thus contribute to the cooling of the planet. Cloud cover thus plays an important role in the energetic balance of the atmosphere and a variation of it is a consequence of and to the climate change expected by recent studies.’ [bold added]
    http://en.wikipedia.org/wiki/Cloud_cover#Role_in_the_climate_system

    ‘As noted by Dr. Roy Spencer,
    “The most obvious way for warming to be caused naturally is for small, natural fluctuations in the circulation patterns of the atmosphere and ocean to result in a 1% or 2% decrease in global cloud cover. Clouds are the Earth’s sunshade, and if cloud cover changes for any reason, you have global warming — or global cooling.” ‘
    http://hockeyschtick.blogspot.co.uk/2014/08/new-paper-finds-changes-in-cloud-cover.html

    Cause and effect questions usually follow.

  4. ntesdorf says:

    “It’s a measurement that, over time, could help scientists studying how the reflectance of the sun’s energy back into space can impact Earth’s changing climate.”
    Also, hopefully, it could convince them that their present Climate Models are so primitive, static and lacking in the full range of mechanisms that they need to scrap them and start over again. They could also start to check the new Models against reality to see if they are even half-way credible.

  5. Curious George says:

    The Terra and Aqua satellites have covered the globe up to about 60 degrees latitude for years. Would it be possible to extract cloud cover data from that archive?

  6. oldbrew says:

    George: NASA says the new EPIC camera ‘will capture the full face of Earth in a single image, something previously done only by the Apollo 17 astronauts and the Galileo mission on its way to Jupiter. Satellites in closer orbits get only a fraction of this view, so scientists have to piece images together to get the whole picture.’

    http://www.climate.gov/news-features/climate-tech/science-space-new-satellite-could-bring-climate-dscovries

  7. oldbrew says:

    A new study ‘shows that sulphur emissions do indeed result in smaller cloud droplet size, leading to brighter clouds that reflect significantly more sunlight.’
    http://www.reportingclimatescience.com/news-stories/article/sulphur-emissions-shrink-cloud-droplet-size.html

    ‘The results may help understand humans’ impact on clouds. Human pollution since the Industrial Revolution is believed to have altered skies in the Northern Hemisphere. One uncertainty in climate models is how much human pollution has brightened the clouds, shielding the planet from the effects of the simultaneous rise in carbon dioxide.’

  8. JKrob says:

    “…Satellites in closer orbits get only a fraction of this view, so scientists have to piece images together to get the whole picture.’
    “…This measurement is important in calculating Earth’s energy balance for climate studies, as well as for tracking weather. For example, hurricanes show up as a high spiral of clouds surrounding a clearly visible eye.”

    That is not correct. Geostationary wxsats to it every 15min.

    Sorry, except for the UV spectrum & Solar monitoring (other valid mission of DSCOVR), I’m not buying the ‘fluff’ PR. What is it doing that the constellation (2 US, 1 European & Japanese and, more recent, China & Russia over the Indian Ocean) of geostationary wxsats have been doing, all at the same time, since at least the 1970’s?

    Not impressed…

  9. oldbrew says:

    NASA says: “With EPIC, you see cloud structure from sunrise on the left to sunset on the right,” said Jay Herman, EPIC instrument lead investigator at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and the University of Maryland, Baltimore County. “It’s the only view we have like this where everything is at the exact same instant in time, even though the local times are different.” [bold added]

  10. DD More says:

    OldBrew – study ‘shows that sulphur emissions do indeed result in smaller cloud droplet size, leading to brighter clouds that reflect significantly more sunlight.’

    I take that as increased sulphur emissions, so Decreased sulphur [mandated by the Clean Air Acts] would logically “result in larger cloud droplets, leading to dimmer clouds and reflect less sunlight”.

    Put that together with your Dr. Spencer – “The most obvious way for warming to be caused naturally is for small, natural fluctuations in the circulation patterns of the atmosphere and ocean to result in a 1% or 2% decrease in global cloud cover. Clouds are the Earth’s sunshade, and if cloud cover changes for any reason, you have global warming — or global cooling.”

    And that is how you have AGW.

  11. JKrob says:

    “… where everything is at the exact same instant in time, even though the local times are different.”

    That makes no sense. Again, except for the imaging in UV bands, why is this of value over & above what is already being done? I don’t need anyone restating what it is doing – that is obvious. I want it explained why this method of imaging is *better* that current geostationary imaging.

    Remember, light that strikes the Earth from the Sun does not get directly reflected back *only* to the Sun, it goes in all directions. So, would a satellite at perpendicular angles to solar directed energy, see the same reflectance (sp?) as a satellite positioned where DISCOVR is? I think not…but it is valid data. Geostationary imaging satellites are the best (IMO) at *seeing* that continually changing reflectance angle. However, I do understand there is no ‘perfect’ way to see & measure ‘all’ of the reflected SW energy off of a 3d oblate spheroid😉

  12. ren says:

    Index of El Niño highest on record.

  13. jim says:

    I’m really at a loss here. I realize that scientists must be above the average kindergarten educational level. But have we dummed down the level of a scientist that far into specialized categories? A picture every two hours is classed as real-time? When we have the advantage of real streaming cameras in space in synchronous orbit already. It seems as if they must have to ask the wrong questions to get funding. That system they put up would have been a more interesting one if it had aanotherr question attached. Such as, input values from the giant ball of fire opposite the view.

  14. oldbrew says:

    What else does it do?

    ‘The satellite’s primary mission is monitoring space weather, but it is also carrying a critical climate-science instrument: a radiation monitor that will measure the amount of energy reflected from and radiated by Earth. The new device, nicknamed NISTAR, will give scientists the most exact measurements they’ve ever had of the amount of energy being trapped in Earth’s atmosphere by greenhouse gases.’
    http://www.climate.gov/news-features/climate-tech/science-space-new-satellite-could-bring-climate-dscovries

    ‘Energy trapping’ – a dodgy concept some might say.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s