EPIC views of Earth finally providing some useful science

Remember Al Gore’s old pipe dream TRIANA which was basically going to be little more than a webcam looking at Earth, which was an idea he came up with right after he “invented the Intenet”? It sat in a warehouse for a decade, and was dusted off and re-purposed in 2015. It’s finally providing some useful science. From NASA Goddard:

NASA’s Earth Polychromatic Imaging Camera (EPIC) sits aboard NOAA’s Deep Space Climate Observatory (DSCOVR) satellite at the Lagrange point 1, one million miles away from Earth. EPIC has been imaging the sunlit side of Earth between 13 and 22 times a day since 2015. Now, new data products track specific elements of our home planet’s atmosphere and plant life, such as ozone in the stratosphere, the makeup of clouds and the health of vegetation on land.

The Earth Polychromatic Imaging Camera (EPIC) instrument operates aboard the National Oceanic and Atmospheric Administration’s (NOAA) Deep Space Climate Observatory (DSCOVR) satellite, which launched in February 2015 and observes Earth from a distance of about one million miles toward the Sun, allowing for observation of the entire Earth from sunrise to sunset.

A spectroradiometer, EPIC acquires images using 10 filters that detect light covering a wavelength region from the ultraviolet to the near-infrared. NASA has made publicly available daily color images that the instrument has been capturing of the sunlit Earth since June of 2015, and now following suit are a collection of science products: sulfur dioxide from volcanic eruptions, total column ozone, ultraviolet (UV) aerosols, cloud and vegetation properties and atmospheric correction including surface reflectance. Those data are available from June 2015 to about two days before the current date.

NASA’s existing fleet of Earth-orbiting satellites provides observations of those and other quantities, enabling scientific research on how the planet is changing. The newly available EPIC products will complement those observations because of the instrument’s ability to capture more images of the entire planet during daylight than any instrument on NASA’s other satellites. In the summer, EPIC captures on average one image every hour and one image every two hours during winter.

“Given EPIC’s special vantage point and frequent observations, we are able to observe the daytime portion of the daily cycle of many phenomena,” said NASA’s Alexander Marshak, deputy project scientist for the DSCOVR mission at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “For example, EPIC can follow a volcanic eruption or a fire plume during the entire day. These measurements complement those taken by other low Earth-orbiting satellites, which view a particular location less often, in many cases only once or twice per day.”

The UV aerosol product tracks phenomena such as plumes from wildfires as they travel hundreds and sometimes thousands of miles and impact everything from air quality to precipitation. Likewise, the sulfur dioxide product tracks volcanic emissions, which can affect air quality and air transportation around the globe, while the ozone product monitors concentrations of this UV-absorbing gas—important to both plant and animal life.

The vegetation product provides information related to plant health and canopy coverage. The Normalized Difference Vegetation Index (NDVI) measures the concentration of chlorophyll in leaves, which is indicative of plant stress and vitality, as plants need chlorophyll to convert energy from the Sun into nutrients. The Leaf Area Index (LAI) projects the amount of leaves over a given area and is important for estimating canopy cover for forest and other studies. While other remote sensing instruments also provide data on NDVI and LAI, EPIC is the first to provide the Sunlit Leaf Area Index (SLAI). “Both LAI and SLAI are key parameters in many global climate, hydrology and ecology models,” Marshak said.

The cloud dataset provides a number of details, including cloud height and thickness, which are important for climate studies and weather analysis and can complement data from other remote sensing spacecraft. Geostationary satellites, such as the GOES-16 spacecraft operated by NOAA, can also observe clouds throughout the day but cannot capture much of the areas near the North and South Poles. But EPIC’s unique positioning in space allows the instrument to capture the Arctic Circle in the northern hemisphere summer and Antarctica during the northern hemisphere winter.

The atmospheric correction dataset provides quantitative information about the amounts of aerosols in the atmospheric column, and it also removes the effects of atmospheric absorption and the scattering of sunlight, providing images of Earth’s surface as if observed without the atmosphere.

The EPIC instrument is one of a suite of instruments housed aboard the DSCOVR satellite. The primary objective of the DSCOVR mission, a partnership between NASA, NOAA and the U.S. Air Force, is to maintain the nation’s real-time solar wind monitoring capabilities, which are critical to the accuracy and lead time of space weather alerts and forecasts from NOAA. The DSCOVR mission was planned as a two-year mission with fuel to last five years.

For more about the EPIC instrument and the science products, visit: https://epic.gsfc.nasa.gov

For more about NOAA’s DSCOVR satellite, visit:

https://www.nesdis.noaa.gov/content/dscovr-deep-space-climate-observatory

Advertisements

37 thoughts on “EPIC views of Earth finally providing some useful science

  1. I’m not sure I understand how it can see “Tiny particles in the atmosphere” from 1M miles away.

    Can someone explain please.

  2. 1 million miles away ? these are some nice pictures, but they are not from 1 million miles away. The distance of the moon varies from about 220,000 to 240,000 miles. Therefore the Lagrangian points must be closer, maybe around 180,000 miles (I am guessing). NASA is getting really sloppy on these details. Maybe on other things too?

    • There are to sets of 5 Lagrangian points. One is Earth/Sun and second is Earth/Moon.
      There is only one Lagrangian point closer to Earth than the Moon and it’s Earth/Moon L- 1.
      Earth/Moon L-2 is behind the Moon. L-4/5 are 60 degree ahead and behind the Moon in it’s orbit with L-3 opposite side of orbit of Moon. Or roughly these three points same distance from Earth as the Moon is.

      Anyhow this Satellite is in Earth/Sun L- 1 which about 1.5 million km away from Earth and on direct line to the Sun.
      And Earth/Sun L-2 is about 1.5 million km from Earth and on line of sun to earth [opposite direction from Sun]. L-4/5 are 60 degrees ahead and behind Earth on orbital path, and L-3 is behind the Sun on Earth’s orbital path.
      So furthest L- point from Earth is Earth radius distance from sun: 149.6 million km times 2 = 299.2 million km away from Earth. Next furthest away are Earth/Sun L 4 and 5. And 60 degree is 1/6th of 360 degree, so one 1/6th the circumference of Earth orbit of the Sun. Or 299.2 times pi and then divide by 6 = 156.6 million km to the 5 or 4 L point from Earth.

  3. It’s amusing that Al Gore likes satellites so much. It seems to me that Gore complained to either Christie or Spencer that their satellite data was the only thing that stood in the way of the complete acceptance of global warming (I can’t find the quote).

    • Geological history shows Earth is expressing a natural variability range (i.e. WX cycle noise is being claimed to be “climate change”, formerly “greenhouse”, plant food is bad … blah-blah-blah) is a bit of a fly in the ointment, too. They could always purge out the geos and burn their libraries but I dunno what the Gaia-tards do about the rocks that constitute Earth itself.

      “Geo is spoiling our Geo-religion!”

      Alternatively, we could ignore them and cut of all funding of the UN (I don’t mean just the IPCC).

      Let them privatize the UN, and we’d all see they’re just money-sucking BS-queens at their core.

      • Maybe not a bad idea but I think just the threat of a significant funding reduction would be enough to force the U.N. to clean up the IPCC and it’s induced garbage science.

  4. Okay, I cannot find this answer anywhere – does anyone know why they only get half the number of images during winter* as they do during the summer?

    The small distance difference in the Earth-Sun L1 point cannot explain such a huge change in image frequency. My only idea that seems to make sense is that they double the resolution in the summer, as there is more “interesting stuff” on land than in the ocean?

    * I assume that this means, with a most politically incorrect attitude, “winter” as seen by the Northern Hemisphere. My most abject apologies, on their behalf, to our friends who reside south of the equator.

  5. Okay, I cannot find this answer anywhere – does anyone know why they only get half the number of images during winter as they do during the summer?

    Probably because the thing is powered by solar panels….

    …I’ll get my coat..

    • We can see the moon – sometimes.

      https://wattsupwiththat.com/2016/07/17/al-gores-revamped-triana-satellite-catches-the-moon-photobombing-earth/

      The moon is some 238,000 miles away from the Earth. At maximum extent, the moon is some 30 Earth diameters away. If EPIC were able to image the Earth and moon simultaneously, the camera would need much lower power lens and have much lower resolution.

      When the moon is in conjunction with the Earth, then the moon’s orbit, tilted some 5 degrees relative the Earth, keeps the moon out of the image. If the moon didn’t have that 5 degree tilt, then all new moons would feature a total or annular solar eclipse and they’d be a whole lot easier to get to.

      The maximum offset from that tilt is harder to do in my head, I’ll leave it for you to calculate.

    • Much of the Earth’s land, especially near the equator, is desert and hence not green. I see green in southern Africa, Europe (except for Spain), eastern US, most of South America. However, much of the land is obscured by clouds.

  6. A picture is worth a billion words. I remember when this went up 3 years ago, and happy to see that it is getting great pics and hopefully even better data. I hope this can somehow measure albedo and cloud cover down to fractions of a percent. Along with other GEO and LEO sats, hopefully this will shed the all important question of what really drives short term climate change and global warming/cooling. My bet is on short term cloud cover driving solar insolation to the surface. But then, what drives short term cloud cover? I think all these questions and more will be answered in the next 20-25 years. What a time to be alive!

  7. Why did they waste the money to launch this dinosaur into space? 4 megapixel camera!?!? One picture from one filter every ten seconds?!?! Couldn’t they have at least have upgraded the camera, etc., before launching this? What a wasted opportunity and wasted expensive rocket – probably with the political intention of giving Gore some attention.

    • Calm… Calm…

      EPIC is only one instrument among many on the platform. It is also a solar weather observatory.

      The camera undoubtedly could take more pictures, but the problem is bandwidth. It is sending all of the data, not just the picture, via plain old low resolution radio waves. Which it has to send at a relatively high power (not many wi-fi hot spots out that way to boost the signal along).

  8. The DSCOVR spacecraft is not “parked at Lagrange 1.

    From space.com: L1, L2 and L3 are all unstable points with precarious equilibrium.

    From wiki DSCOVR: At this location it has a continuous view of the Sun and of the sunlit side of the Earth. The satellite is orbiting the Sun–Earth L1 point in a six-month period, with a spacecraft–Earth–Sun angle varying from 4 to 15 degrees.

    Which is why sometimes you see the moon crossing in front of the earth but mostly do not. Here the moon crosses in front of the earth: https://epic.gsfc.nasa.gov/?date=2016-07-05 and here just the shadow of the moon crosses the Earth: https://epic.gsfc.nasa.gov/?date=2017-08-21 Interestingly the shadow cast by the moon is smaller than you would expect.

  9. Finally, a correct measurement of Earth’s albedo over the course of several years, as we can see the average and standard deviation, will be invaluable to the effort to determine Climate Sensitivity.

    Both Transient and Equilibrium Climate Sensitivity might be quite low. Svallgard’s post earlier today on the other thread certainly agrees with this.

    The Alarmist’s position could go up in smoke immediately after an accurate figure for Albedo is determined.

    Once again, increasing C02 raises the altitude at which the Atmosphere freely radiates to Space, lowering the temperature at which the Atmosphere freely radiates to Space, slightly increasing the amount of energy retained in the Atmosphere.

    Do not be fooled by talk of “shoulders” and “pressure broadening.” These phenomena, while real, only lower the height at which the Earth’s infrared outgoing radiation is absorbed and thermalised, already around 10 meters, might lower it to 9.9 meters, and has been saturated at this altitude for millenia.

    No one can calculate this effect of raising the altitude at which the Atmosphere freely radiates to space. All attempts at calculating Climate Sensitivity are based on the assumption that all warming since 1850, or 1880, or some year, are due to AGW. There is no proof, and this assumption is completely unscientific. Natural variability remains substantial.

Leave a Reply

Your email address will not be published. Required fields are marked *