Global Dataset Download Report August 14 th, 2009

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1 Global Dataset Download Report August 14 th, 2009 Description The task was to download the daily data from the sensor MOD09 and from LTDR to use later for analysis. The data to acquire started from the date February 24 th, 2000 and it was downloaded up until the 10 th of July, 2009 for MODIS, for LTDR the first date was the 195 th day of 1981 until the 31 st of December of As part of the task, the gaps between the data had to be identified and logged to have a more accurate database. FTP Source The MODIS data was acquired from the following NASA site: ftp://e4ftl01u.nascom.nasa.gov/molt/mod09cmg.005/ The LTDR data was obtained from the site: ftp://ltdr.nascom.nasa.gov/pub/f301/avhrr/ver2/ The program that was used to download the data was wget with the options of -rc which are recursive download and continuous. Data Information The daily global data from MODIS and LTDR both have 3600x7200 pixels. An example of what an HDF file contains is shown in the table on page 4 and 5 (Page 4 for MODIS and Page 5 for LTDR) Screenshot of the file MOD09CMG.A hdf which corresponds to the file of June 1 st 2006 using the channels 1,4,3 (R,G,B).

2 Screenshot of the file AVH09C1.A N hdf which corresponds to the file of July 14 th 1981 using the channels 2,1,1 (R,G,B). Data availability In the following table are the days that do not have any data and a total and subtotal of how many days do have available data to download. Note that the year 2009 has many missing days since it is the current year and the data is not available yet. All years were considered as Leap Years and added one in the No Data field in order to take into consideration the three Leap Years of which we have data. The following table is for the MOD09CMG data. Please refer to the table attached for a list of every missing day of the MODIS data. Year Days with data No Data 2000(Leap Year) (Leap Year) (Leap Year) * SUB-TOTAL TOTAL 3660 * 2009 = Data not available yet

3 The following table shows the days with no data for AVHRR 09 and AVHRR 13. Year Days with data No Data Missing Days Missing Days ,54,114,183, , , ,140, ,264, (Leap Year) ,15,39,51,62,341,366 *282 (2) ,2, ,73, (Leap Year) , *303(2) (Leap Year) (Leap Year) ,288 Location The MODIS data was downloaded and distributed in 3 places: one computer and two external drives. The computer is mwitu ( ), and the drives are two 1TB external drives. Mwitu: /MODIS/ Here is all of 2000, and parts of 2001 and 2002 o /mnt/dsk2/data/modis/ Here is all of 2003,2004,2005, and some of 2008 External drive mounted on mwitu: o /media/disk/modis/ Here is parts of 2006 and 2007 External drive mounted on Dunia: o C:/cygwin/cygdrive/j/MODIS/ Here is partial data for 2001,2002,2006,2007,2008,2009 The LTDR data was downloaded into mwitu and one external drive, which is mounted on mwitu and can be accessed at the following path: Mwitu: /LTDR/ Here is N07 and N09 External drive mounted on mwitu o /media/disk/ltdr Here is N11 and N14

4 List of SDS contained in every file (MOD09CMG.005): SDS Data type Valid range Scale factor Fill Value Units 1 Coarse Resolution Surface Reflectance Band 1 16-Bit integer -100, reflectance 2 Coarse Resolution Surface Reflectance Band 2 16-Bit integer -100, reflectance 3 Coarse Resolution Surface Reflectance Band 3 16-Bit integer -100, reflectance 4 Coarse Resolution Surface Reflectance Band 4 16-Bit integer -100, reflectance 5 Coarse Resolution Surface Reflectance Band 5 16-Bit integer -100, reflectance 6 Coarse Resolution Surface Reflectance Band 6 16-Bit integer -100, reflectance 7 Coarse Resolution Surface Reflectance Band 7 16-Bit integer -100, reflectance 8 Coarse Resolution Solar Zenith Angle 16-Bit integer 0, degrees 9 Coarse Resolution View Zenith Angle 16-Bit integer 0, degrees 10 Coarse Resolution Relative Azimuth Angle 16-Bit integer , degrees 11 Coarse Resolution Ozone 8-Bit unsigned integer cm atm Coarse Resolution Granule Time 16-Bit integer 0, HHMM 17 Coarse Resolution Band 3 Path Radiance 16-Bit integer -100, reflectance 32-Bit unsigned 18 Coarse Resolution QA integer 0, N/A 0 bit field 19 Coarse Resolution Internal CM integer 0,8191 N/A 0 bit field 20 Coarse Resolution State QA integer 0,65535 N/A 0 bit field 21 n pixels averaged 8-Bit unsigned integer 0,40 N/A 0 Unitless

5 List of SDS contained in every file (LTDR): SDS 1 Surface Reflectance 640 nm 2 Surface Reflectance 860 nm Brightness Temperature microns Brightness Temperature microns Brightness Temperature microns 6 Surface Reflectance 3.75 microns 7 Solar Zenith Angle 8 View Zenith Angle 9 Relative Azimuth 10 Quality Assurance Data type Scale Factor Valid range Fill Value Units integer , N/A integer , N/A Degree integer 0.1 0, K Degree integer 0.1 0, K Degree integer 0.1 0, K integer , N/A integer , Degree integer , Degree integer , Degree integer N/A N/A N/A N/A

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