Getting Started with MODIS Land Surface Temperature Data- (Part 1)
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Getting Started with MODIS Land Surface Temperature Data- (Part 1)


Getting Started with MODIS Version 6
Land Surface Temperature Data Part 1: All About Accessing Data. Presented
by the Land Processes Distributed Active Archive Center or LP DAAC.
This video is part 1 of the “Getting Started with MODIS Version
6 Land Surface Temperature Data” video series. This video will cover
the Land Surface Temperature data products, improvements in Version
6 products over Version 5 products, and how to search for and download
these data using the Earthdata Search Client data access tool.
The LP DAAC distributes several MODIS Version 6 Land Surface
Temperature products. All data distributed by the LP DAAC are
available for download at no charge. These data products provide
information on the temperature and emissivity of the land’s surface.
These products provide 5 minute, daily, 8-day and monthly coverage,
with spatial resolutions of 1,000 and 5,600 meters. MODIS Land Surface
Temperature data products are provided as non-gridded swaths,
as tiled and in sinusoidal projection or as Global Climate
Modeling Grid or CMG products that are projected to a latitude-
longitude grid. Detailed information about each of the individual products
can be found on the LP DAAC website at lpdaac.usgs.gov. The MODIS data
collection is reprocessed into a new version every so often to provide
users with improved products. There are several improvements that
were included in the reprocessing of the Land Surface Temperature data
products. Improvements include: removal of cloud-contaminated land
surface temperature values from both level 2 and level 3 products,
updates to the look-up table for the split-window algorithm, minor
adjustments in the classification based surface emissivity values for
bare soils and rocks, improvements to the tuned day/night algorithm
for a better performance over desert regions, and the addition
of two new 8-day and monthly 6 kilometer gridded Land Surface
Temperature products. More detailed information on the
changes to each of the MODIS Land Surface Temperature products can
be found on the Digital Object Identifier or DOI landing page on
the LP DAAC website. The LP DAAC website also offers several ways
to download MODIS Land Surface Temperature data products. At the
bottom of the DOI Landing Page for each product are links to the
data access tools for the specific data product. In this video,
step-by-step information for downloading data using NASA’s
Earthdata Search Client data access tool will be demonstrated.
From the Earthdata Search home page, search.earthdata.nasa.gov, click
on the “Earthdata Login” button to login with your NASA Earthdata
account. If you do not have an Earthdata account, click on the
register button and follow the prompt to create one. Now, search
for the Terra MODIS Version 6 Monthly Land Surface Temperature 6
kilometer level 3 gridded product, MOD11B3. Type “MOD11B3” in the
search bar and hit enter. Click on the MOD11B3 Version 6 data product.
This will pull up all of the MOD11B3 granules. Parameters for a
specific time and location can be set above the map. For this video
let’s look at Land Surface Temperature in Alberta, Canada
from March 1 to June 30, 2016. First, pan and zoom the map to
Alberta, Canada. Change the temporal range by clicking on
“Temporal” and then click on the Start date to change the date to
“March 1, 2016”. Now change the End date to “June 30, 2016” and
click on apply filter. To change the spatial information, click on
“Spatial” and select “polygon” from the drop down menu. Draw a
polygon around Alberta. You will now see a green outline that
indicates the footprints of the Terra MODIS tiles contained in
your polygon. The granules for the selected time that are located in
the selected area are now listed in the lower left hand corner of
your window. Above the granule list are options to “Retrieve
Collection Data” which allows a user to download all of the
matching granules, an “i” icon to learn more about the data
collection, a filter icon to further filter the data, and a
plus sign icon, which allows a user to add multiple data products
to their Earthdata Search project. Click on the first box in the
lower left hand corner list to select the most recent scene in
the list. This box contains a preview of the granule, the
Terra MODIS filename, the dates of the data, an “x” in the upper
right hand corner to remove the scene from your granule list,
an “i” for more information, and the retrieval icon to
download a single granule. Click on the “i” icon to bring
up the metadata for the selected granule. Remember, metadata are
data about data. The metadata include the DOI, which is
necessary for proper citation, as well as information on the
scene’s corner coordinates, input granules, and more.
Click on the “Metadata” tab for links to download metadata
in different standard formats. Click on “Back to Granules” to
return to the granule list. Click on “Retrieve Collection
Data” to download all of the granules in the granule list.
Now, review the data download order on the “Data Access” page,
this page lists the number of granules in the order and the
size of the order. From here users can select the service
options. Select “download” to instantly receive the granules
in the order or select “Delivery Option” to receive
the granules via email. Click on “Download” and then
“submit” to submit the order. This will provide you with
download links, a data access script or links to browse
images of the data. Depending on the data access method,
the data can be accessed immediately or will be sent
to the user via email. Thank you for watching our
video. For more information on MODIS Version 6 Land Surface
Temperature data please visit the LP DAAC website at
lpdaac.usgs.gov

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