# Presentation: 519504

## Mid-Decadal Global Land Survey

- Jeff Masek
- Biospheric Sciences Branch, NASA GSFC
- Steve Covington
- Aerospace Corporation / USGS
- November 1, 2006

## Mid-Decadal Global Land Survey (MDGLS)

**Follow-on to the GeoCover orthorectified global data sets (1975, 1990, and 2000 epochs)**
**The objective of the Mid-Decadal Global Land Survey (MDGLS) is to extend this series with a new global land survey centered on a 2005-2006 epoch **
- Initiated through CCSP, to support global assessments of land-cover, land-cover change, and ecosystem dynamics (disturbance, vegetation health, etc)
- Landsat-5 TM and Landsat-7 imagery
- Additional Terra ASTER, EO-1 ALI as needed
**The Project has 3 Phases:**
- Phase 1: identify candidate scenes and ingest into the USGS archive
- Phase 2: Process the collected data into an ortho-rectified dataset compatible with previous surveys
- Phase 3:  Analyze data set to quantify trends in land cover and vegetation dynamics

## Mid-Decadal Global Land Survey (MDGLS)

**Phase I:  Identify and Acquire L5 and L7 Data**
- Phase II:  Process MDGLS Data
- Phase III:  Analyze MDGLS Dataset for Land Cover/ Land Cover Change

## Where do we want data?

**Green** 	= GeoCover 2000 Coverage
**Red** 	= New MDGLS Coverage

## When do we want data?

**Green****	**	= NH Summer (Jun, Jul, Aug, Sep)
**Red****  ****	****	**=** **NH Spring (Apr, May)
**Violet****  ****	****	**=** **NH Fall (Oct, Nov)
**Yellow****	****	**=** **NH Winter (Jan, Feb, Mar, Dec)

## What data are available?  Landsat-7

**White**** ****	**= Base Scene < 1%, Fill < 05%
**Yellow** 	= Base Scene < 1%, Fill < 10%
**Green** 	= Base Scene < 5%, Fill < 10%
**Red** 	= Base Scene < 5%, Fill < 20%

## What Data Are Available?  Landsat-5

## Status of Foreign-Source Data

**8 of 10 International Cooperators (IC) have agreed to support the MDGLS**
**6 of 10 ICs have submitted metadata**
**Campaign Station Status**
- Kiruna (ESA) – Offline due to L5 Fixed-Array Con Ops.  72 tapes are at EROS to be ingested
- Moscow and Irkutsk (ScanEx) – Stations are online and providing data operationally
- Chetumal, Mexico (DLR) – Station under construction and due to begin operations in early 2007
- Maspalomas (ESA) – Just beginning station certification.
- Malindi (ESA) – Implementation schedule to be worked
- Hobart (GeoScience Australia) – Coordinating data transfer

## Mid-Decadal Global Land Survey (MDGLS)

- Phase I:  Identify and Acquire L5 and L7 Data
**Phase II:  Process MDGLS Data**
- Phase III:  Analyze MDGLS Dataset for Land Cover/ Land Cover Change

## Phase II Tasks

-  **Process selected data**
- 	- Orthorectification
- 	- Gap-filling (for Landsat-7)
- 	- Product format
-  **Distribute MDGLS data**
*Complete dataset available Fall 2008*

**Phase II Tasks**

## Data Source Selection:  Issues

**Landsat-7****	****	****	****   Landsat-5**

-  Better radiometry
-  60m TIR band, pan band
-  Gaps can be filled in cloud-free conditions

-  No gaps
-  L7 gap filling can result in radiometric artifacts
-  L5 calibration improved for ~2000 to present

**Tested ETM+ gap-filled products for change detection**
*	**- Jim Vogelmann – mapping pivot irrigation*
*	**- Matt Hansen – tropical deforestation*
*	**- Chengquan Huang – temperate forest disturbance*

## Landsat-7 Gap-filling:  The Good

**Northern Siberia (p159r15)**

**Landsat-7 Gap-filling:  The Good**

**EROS Gap-filling works very well in cloud free conditions**

**primary**

**fill**

## Example:  1999-2005 forest disturbance, VA

- 2005L7GF-1999GeoCover

- Overall agreement = (145710/160000)  91.0687%
- Agreement matrix

| Class | forest | non-forest | forest loss | forest gain | Total | Producer's (%) |
| --- | --- | --- | --- | --- | --- | --- |
| forest | 67808 | 2 | 1821 | 355 | 69986 | 96.9 |
| non-forest | 46 | 51664 | 111 | 4484 | 56305 | 91.8 |
| forest loss | 2364 | 123 | 7095 | 180 | 9762 | 72.7 |
| forest gain | 999 | 3547 | 258 | 19143 | 23947 | 79.9 |
| Total | 71217 | 55336 | 9285 | 24162 | 160000 |   |
| User's (%) | 95.2 | 93.4 | 76.4 | 79.2 | Overall (%) = | 91.1 |

**Example:  1999-2005 forest disturbance, VA**

- Towards SE of scene edge, no obvious visual artifacts in gap filled areas

## Example:  Amazonian Forest Clearing

- L7 Geocover

- L5 from INPE

- L7 gap-filled from EROS

**Example:  Amazonian Forest Clearing**

## For cloud-free areas, results are very similar

- L7 to L5

- L7 to L7 slc-off

**For cloud-free areas, results are very similar**

- Green=forest to forest, beige=non-forest to non-forest, red=forest to non-forest

## Landsat-7 Gap-filling:  The Bad and the Ugly

**Landsat-7 Gap-filling:  The Bad and the Ugly**

**Honduras (p18r50)**

**Gap-filling with cloudy scenes can introduce radiometric artifacts; small residual gaps are possible**

**primary**

**fill**

**residual gap**

## Example:  1999-2005 forest disturbance, VA

- 2005L7GF-1999GeoCover

- Overall agreement = (123482/158223)  78.0430%
- Agreement matrix

| Class | forest | non-forest | forest loss | forest gain | Total | Producer's (%) |
| --- | --- | --- | --- | --- | --- | --- |
| forest | 59803 | 174 | 12384 | 2311 | 74672 | 80.1 |
| non-forest | 6 | 21942 | 212 | 6011 | 28171 | 77.9 |
| forest loss | 2719 | 188 | 7038 | 502 | 10447 | 67.4 |
| forest gain | 549 | 9065 | 1136 | 34183 | 44933 | 76.1 |
| Total | 63077 | 31369 | 20770 | 43007 | 158223 |   |
| User's (%) | 94.8 | 69.9 | 33.9 | 79.5 | Overall (%) = | 77.7 |

- Towards SW of scene edge, gap filled with cloud/shadow contaminated pixels

**Example:  1999-2005 forest disturbance, VA**

## Data Source Selection:  Status

*	*
**Recommendation:  **
-    - For cloud-free scenes:  lean toward Landsat-7 ETM+
-    - Cloudier scenes:  lean toward Landsat-5 TM
-    - Humid Tropics:  multiple ETM+ acquisitions for compositing
**Sensor choice must be balanced against acquisition date, overall cloud cover, and acquisition date of 2000 Geocover**** **
-    - Optimization algorithm being developed to assist selection

## MDGLS Product Specification (Draft)

-  UTM / WGS-84 projection
-  14.25 / 28.5/  57 meter resolution
-  Cubic Convolution resampling (1 step)
-  GeoTiff format
-  Orthorectified, Gap-filled
- Processing by USGS EROS
- FTP distribution of individual MDGLS scenes at no cost, with limited provision for bulk distribution of entire dataset (e.g. via hard disk transfer).

## MDGLS Orthorectification

- Use 2000 GeoCover chips as geodetic control, SRTM 30/90m for terrain correction
- 	- L7 automated 1Gt processing available Feb 2007
- 	- L5 automated 1Gt processing available late 2007
- Also recommend reprocessing of previous GeoCover datasets in high-relief areas to maintain continuity with MDGLS
- 	- model absolute error due to Geocover 	DEM choice
- 	- reprocess locations with errors >60m 	using SRTM

## MDGLS Schedule

**CY 2007**

**CY 2008**

- Image Acquisition

- Phase 1 Activities

- Scene Selection

- *IC = International Cooperator

- IC Data Collection

- Phase 2 Activities

- Phase 2 Planning

- Product Generation

- IC* Metadata Collection

- Product Generation

- Prime Acquisition Period

**CY 2006**

**CY 2005**

**CY 2004**

## Near-Term Schedule

- November 2006

- Post draft MDGLS Data Product Specification and Implementation Plan for public comment

- Final Spec and Implementation Plan

- Finalize scene selection for North America

- Begin processing North American ETM+

- December 2006

- February 2007

- February 2007

## Mid-Decadal Global Land Survey (MDGLS)

- Phase I:  Identify and Acquire L5 and L7 Data
- Phase II:  Process MDGLS Data
**Phase III:  Analyze MDGLS Dataset for Land Cover/ Land Cover Change**

## Phase III:  Land Cover Dynamics

- Following Jan 2006 MODIS meeting, a small team put together a draft white paper describing a requirements for a Land Cover / Land Cover Change Earth Science Data Record (ESDR).
- Four elements described:
- 	Global 1km land cover type @ 5 years
- 	Global 1km continuous fields @ year
- 	Global 30m land cover type @ 5 years
- 	**Regional -> global 30m land cover change/disturbance**

**The MDGLS dataset offers a “pilot” opportunity to assess global rates of land cover change for 2000-2005.**

## Recommended Approaches

**Produce products via independent teams, but coordinate tools and class definitions**
-    - regional to continental scales
-    - thematic projects (e.g. global urbanization)
**Prioritize regions with known LC dynamics of critical import for carbon, water, biodiversity, and societal services**
**Land cover is necessary but not sufficient; include vegetation dynamics (disturbance, recovery, fragmentation, biome migration, etc). **
**Establish concurrent validation program **

## Woody Plant Cover, N. Texas

- 0%	   	          100%

- 1937		1999

- Forest Disturbance, Oregon

## Slide 27