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The MODIS L1 Viewer allows you to visualise either image or fire
data from the MODIS satellites (Aqua and Terra) as sent over the EUMETCast system (you will need
to register with EUMETSAT to get this additional data, but it is free). The data
is sent in 5-minute segments, and the program allows you to combine multiple
5-minute segments from the same pass to produce a combined image. Both the
raw data, and several derived coloured images are available.
Functions
Browser view
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(Click for a larger image)
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The Browser tab provides a graphical display of all the
data available for a particular date, allowing easy selection of a segment
to be processed. Ascending and descending passes are shown in
different colours, each labelled with the time of the segment.
Double-click a segment to open it for further viewing. You can also
display the user-defined regions to which data can be remapped.
Select the date and time either with a calendar control, a
"today" button, or by stepping day-by-day.
The Browser View allows you to select multiple images
from the same pass for processing as a combined pass covering more of the
Earth's surface. You can drag-and-drop file from Windows Explorer
onto the Browser tab.
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Raw Images display
Once you have selected one or more segments for
processing, the Raw Images tab is where the data is first displayed.
There is a Geo tab to show the region covered by the pass in more detail,
and a number of tabs allowing access to one of the 18 - yes, eighteen -
sensor channels available from MODIS. There are 36 channels from the
sensor itself, of which 18 are available on the EUMETCast subset.
Visible channels
- 1 - 620-670nm
- 2 - 841-876nm
- 5 - 1230-1250nm
- 6 - 1628-1652nm
- 8 - 405-420nm
- 9 - 438-448nm
- 10 - 483-493nm
- 12 - 546-556nm
- 15 - 743-753nm
- 26 - 1.360-1.390µm
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Thermal channels
- 20 - 3.660-3.840µm
- 23 - 4.020-4.080µm
- 27 - 6.535-6.895µm
- 28 - 7.175-7.475µm
- 29 - 8.400-8.700µm
- 31 - 10.780-11.280µm
- 32 - 11.770-12.270µm
- 33 - 13.185-13.485µm
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Right-clicking any of the images allows you to:
- Add boundaries.
- Display the North Pole.
- Select a region to which to remap the data.
- Change the brightness of a visible-channel image.
- Zoom in or out.
- Save the displayed image, either with or without
horizontal geometric correction.
Derived Images display
The Derived Images tab allows access to a variety of
channel combinations designed to bring out various environmental
parameters based on physical characteristics of the atmosphere and
land. In the first release, the following are provided, and it is
expected that more will be added as the program is developed:
- RGB - colouring resembling the classic RGB421 display
from NOAA AVHRR data.
- RGB521 - experimental colouring to bring out snow.
- Vegetation - vegetation index derived from channels 1
and 2, with the vegetation coloured green.
- Air mass - derived from the thermal channels to show
bulk atmospheric characteristics.
- Ash - derived form thermal channels processed to emphasise
ash and dust. Also shows aircraft trails as dark lines.
Similar right-click options are available. Here are some
sample images, with even the large images shown at 2km resolution. The
MODIS L1 Viewer allows you to interpolate the images down to 250m resolution,
64-times greater than the images shown. Click any image for a larger view.
Fire
Allows for display of MODIS fire data - files sent on
data channel 12 with names like: MOD14.A2010214.0115.hdf. You
can right-click the images to change the displayed area.
Setup options
The various setup options allow the selection of
boundary data and its colour, definition of the regions for remapping, and
various processing and image save options.
Can I register and what do I get?
The program includes a 30-day trial licence period to allow
you to evaluate its function. After the 30-day period, you will need to
register to continue running the program. Registration also entitles you
to technical support. Register the
MODIS L1 Viewer here.
Download the MODIS L1 Viewer
| V1.0.2 |
New program to display and process MODIS L1
Images and Fire Data being sent over the EUMETCast service (registration
with EUMETSAT may be required). The MODIS L1 Viewer allows you to
browse received passes graphically, and to select one or more segments for
processing. Both the raw data and derived multi-channel sensor
combinations can be viewed, allowing better interpretation of the data,
and both the raw and derived data can be remapped to regions of your
choice at a variety of resolutions.
Many thanks to all the
beta testers and those who helped shape this new software.
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| V1.0.4 |
Support colour lookup tables (CLUTs) on
thermal data, add "dust" day/night derived product, add
mouse-drag for image image location, improved "Geo" display of
multi-segment passes, start foreign-language support (French translation
started, German pending, Italian done).
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| V1.0.6 |
Add second city list option, make right-click, Vis ch. brightness act on vegetation,
clarify how to show boundary and cities, work with new MODIS file names (browser updated,
File|Open dialog updated), French & Italian language updates.
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| V2.0.2 |
New version so a licence upgrade is required, support new Terra data and file names, allow open of multiple fire files, option to show region where data is available.
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EUMETCast updates
There are changes which you might need to make to
your EUMETCast configuration:
Enable data channel 4
If you are already receiving the "hourly FSD", there
is no change to make. Otherwise, add lines to your recv.ini such as:
[EUMETSAT Data Channel 4]
target_directory=received\Data Channel 4
The exact location for the received data may be different for
your system.
It is EUMETSAT’s recommendation that your FSY data is allowed 300MB, so increase your RAMdisk to 300MB, and alter the relevant line in your recv.ini file to read:
[parameters]
file_database_size=300000000
Note that if you are running the earlier AR-Soft RAMdisk, you
will need to uninstall it (run the install program and select the uninstall
function), and install the Dataram
RAMdisk software instead.
For the MODIS fire data - enable data channel 12
If you are already receiving data channel 12, there
is no change to make. Otherwise, add lines to your recv.ini such as:
[EUMETSAT Data Channel 12]
target_directory=received\Data Channel 12
The exact location for the received data may be different for
your system. This will also provide the AIDA-1 and TAMSAT data if you have
requested these.
If you have downloaded MODIS images from the Web site, you may
have noticed that there is an apparent duplication of data at the edge of the
image, and that the images are not corrected for the variation in resolution
between the centre and edge of the image. To correct these defects, I
offer the unsupported Defrag MODIS program.
The snows of early December 2010 when, on Monday December 6th, much of
Central Scotland was brought to a halt by heavy snow showers, on top of previous
snow compacted to ice. Temperatures were not above freezing for days
before and after. Here the Vegetation mode of the program has been used,
together with the the brightness adjustment for vegetation added in beta
1.0.5.83.
Here's another
image from Wednesday, 2010 December 08 - both images copyright 2010
NOAA/NASA/EUMETSAT etc.
Here is an example of the program processing multiple thermal
channels of data to highlight the volcanic ash from the eruption of
Eyjafjallajokull in Iceland in Spring 2010. The ash shows as a bright pink
band in the image below, and you can also see aircraft "contrails" in
a darker grey colour to the north of Iceland. Note that the colour can
vary according to the nature and concentration of the ahs, so use care when
interpreting such an image. This image is one of many you can find on James
Brown's splendid Ash Web page. © EUMETSAT (2010). This MODIS
image was taken 0410 on Thursday May 6th 2010 - click
for more like this.
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Download the 
