US Remote Sensing Capabilities

Chris Justice and John Townshend

NASA’s Earth Observing System

& Related Satellites

Next Generation Missions

Relevance to Land of US assets

• In fact relatively small number of assets directly relevant to land

• MODIS• VIIRS• Landsat• Also we need a “VCL” type instrument for the vertical

dimension in vegetation – Just possibly may be revived.

• Plus we need regular very high resolution data for scaling and validation which potentially could be provided by US commercial satellites

Imagery (with four ARRs)Sea Surface Temp

Aerosol Optical ThicknessAerosol Particle Size

Suspended MatterCloud Cover/Layers

Cloud Effective Particle SizeCloud Optical Thickness

Cloud Top HeightCloud Top Pressure

Cloud Top TemperatureAlbedo

Land Surface TemperatureVegetation Index

Snow Cover/DepthSurface Type (ST)l

Fresh Water Ice(Sea Ice ARR)Ice Surface Temperature

Ocean Color/Chlorophyll Sea Ice Characterization

Active Fires (ST ARR)Precipitable WaterCloud Base Height

Net Heat FluxSoil Moisture

IA

IIA

IIB

IIIB

VIIRS EDR Priorities & Performance

Visible/IR Imager Radiometer Suite

CY 99 00 11 12 13 14 15 16 17 1803 08 09 1001 02 0704 05 06

Local Eq

uato

rial C

rossin

g T

ime

S/CDeliveries

S/C delivery interval driven by 15 month IAT scheduleLast Modified: Dec 1, 2001 6

1330

0930 - 1030

AVHRR

EOS-Aqua

VIIRSC2N’

NPOESS

AVHRR METOP-AVHRR

VIIRSC1

N

M

16

10-Year Mission Life for NPOESS

AVHRR-VIIRS Transition Schedule

NPPEOS-Terra1030

Landsat data

• Landsat class data with the Landsat 7 acquisition strategy (LTAP) has been highly successful in satisfying multiple user needs– GLCF has regular downloads of 25,000 +

scenes per month.

• But Landsat now has major problems.

Landsat 7 has significant problems for

change detection.

• Scan Line Corrector failure means that only the central 28 kms has no missing data.

• In fact this still means that 78% of the data is collected.

• But the 22% not collected is NOT the same 22% on each image and hence change detection is significantly compromised.

Landsat 7 fixes 1. Enhanced SLC-off Browse Image

• The Landsat 7 browse image displayed on all data ordering interfaces has been modified to allow users to estimate the width of potential SLC-off scan gaps over their area of interest.

2. User-Selected Interpolation• Users will have the ability to select the number of pixels that are interpolated across the data gaps during

Level 1G processing. This will allow potential production of a fully populated image when specified by the user.

3. SLC-off Data Available through NLAPS• Users will have the option to purchase National Landsat Archive Production System (NLAPS) processing if

desired.

4. Gap-filled product - Phase 1 (SLC-off / SLC-on Merge)• An initial (Phase 1) gap-filled image product will be generated by replacing the missing data of an SLC-off

scene with pixel values derived from a coregistered, histogram-matched SLC-on scene. product.

5. Gap-Filled Product - Phase 2 (SLC-off / SLC-off Merge)• A second (Phase 2) gap-filled image product will be generated from the merge of two or more SLC-off

scenes to produce a single image product.

6. Inclusion of band-specific Gap Mask

Can Landsat be replaced with existing assets?

• SPOT HRV and IRS can provide data with ground receiving capability.

• Some efforts already to do this, though very slow response from the US.

• Unclear if resultant products are truly interoperable, but probably acceptable.

• But far from global coverage and the quality of acquisition strategy will be below that of Landsat.

IRS-1C/1D LISS-3 data archive of R&D Center ScanExIRS-1C/1D LISS-3 data archive of R&D Center ScanEx(February, 2004) (February, 2004)

Availability of the historical record

• Almost complete global coverage for the early 90’s and 2000 available through NASA/Earthsat’s Geocover initiative

• Available on-line through the GLCF and through TRFIC

• Made available to countries (though UNEP and FAO)• Very valuable data set but with significant

limitations.– Timing of acquisition varies substantially– Varying phenology hinders change detection

What is the quality of the data: analysis for southern Africa of the quality of FAO proposed 1 degree sample 10km squares

Analysis of suitability of GeoCover images for 1990 for Southern Africa by GLCF

• Total Number: 308• Fully acceptable 180• Restricted value due to cloud

etc 89• Unacceptable 39• Hence historical record is

less satisfactory than at first appears

What can we learn from these issues?

• We do not have the final solution.• We need an operational fine resolution (20-50m) land

observing system – one that is guaranteed in the long-term– POLO Polar Orbiting Land Observer – Possible platform - NPOESS Lite

• Having the assets in orbit is not sufficient: an excellent acquisition strategy is vital

• Avoid moving parts if at all possible.

Enhancements to ETM+ are needed.

• LDCM Science Team for Resource 21made the following recommendations– Add bands especially a Cirrus band (1380nm – Goetz, Gao et al)– Alter bandwidths (lessons learnt from MODIS)

• 10nm reduction (to 680 nm) in upper bound of red band • Narrow and reposition NIR band to avoid water vapor, • Narrowing and repositioning of SWIR2 to the 1560nm to 1660 nm region to

avoid water vapor attenuation. • Shift the SWIR3 to the 2100 nm to 2300 nm region to reduce water vapor

absorption impact.

– Improve the MTF (e.g., average 9x10m bands)– Improve frequency of acquisition (e.g. to 2 days).

Conciliating spatial and temporal resolutions: towards an operational concept for land environment: argues for more

frequent observations at Landsat/SPOT resolutions

MSG

MERIS

MODIS

ERSSPOT

POLDERVGT

SPOT 5

Pléiades

« Gap »

10-20 m spatial resolution8-12 spectral bands2 days revisitFull and operational observation of continents

Landsat

Source: H. Jeanjean

Recent developments• US has at last accepted that a Landsat class capability be regarded as an

operational necessity.• Proposal in recent RFI is to place an ETM+ like instrument on NPOESS.• But this could be 2009 or later. Hence possibility of a major gap.

• May be a earlier launch but resources may not be available.• International effort should be launched to use existing international assets to satisfy LTAP.

• Frequency would drop to once every 17 days.• Suggested enhancements:

• Significantly widen swath (2-3 times)• Additional low cost free-flyers (Surrey Satellite model?) with possibly simpler sensors to

improve temporal resolution and as operational back-ups.• Need reflectance products not DNs. • Also orthorectified products.

Extra slides

• One on a new crop data set though coarse resolution

• Two extra JAXA slides if you need them

Global Distribution of Wheat

Global Data Set of 18 Major Crops

Leff, B., N. Ramankutty, and J. Foley, Geographic distribution of major crops across the world, Global Biogeochemical Cycles, 18, GB1009, 2004. Center for Sustainability and the Global Environment Nelson Institute for Environmental Studies University of Wisconsin-Madison

Derived by merging remotely-sensed global

land cover data with crop census data.

SEA-1 (2 CD set)Mainland South-East Asia Dual-season (Dry/rainy)Mosaicking & SAR processing by NASDA

AM-1 (4 CD set)South America/AmazonDual-season (Low water/high water)Mosaicking by JPLSAR processing by ASF & NASDA

AFR-1 (3 CD set)West & Central Africa and Madagascar

Dual-season (Low water/high water)Mosaicking by JRC

SAR processing by NASDA

NA-1 (DVD)Boreal North AmericaDual-season (Summer/winter)Mosaicking by JPLSAR processing by ASF

AM-3 (2 CD set)Central America/Pantanal

Mosaicking by JPLSAR processing by ASF &

NASDA

GRFM/GBFM Data Sets

SEA-2 Insular South-East Asia (Kalimantan, Java, Sumatra, Sulawesi)Multi-annual (1994/1996/1998)Mosaicking & SAR processing: JAXATarget: April 2004

AU-1AustraliaSingle seasonMosaicking & SAR

processing by JAXATarget: JFY 2004

New Data Sets in the pipeline

SEA-3 Insular South-East Asia (Philippines, New

Guinea)Single seasonMosaicking & SAR

processing by JAXATarget:June 2004

China Single seasonMosaicking & SAR processing by JAXATarget: JFY 2004

AM-4Southern South AmericaSingle seasonMosaicking by JPLSAR processing by JAXA

IndiaSingle seasonMosaicking & SAR processing by JAXATarget: JFY 2004

AFR-2Southern AfricaSingle seasonMosaicking by JPLSAR processing by JAXA