05/01/2011

11:52 AM Task #212: Validate fused DEM at SRTM/ASTER boundary

... Rick Reeves

11:46 AM Task #212: Validate fused DEM at SRTM/ASTER boundary

Here is the output from a set of 'image difference' calculations made using the R script 'SampleDemDiffCols.r",
whic... Rick Reeves

04/29/2011

04:36 PM Task #212: Validate fused DEM at SRTM/ASTER boundary

Was:
gdalwarp -te -135.9880605 58.4644470 -101.3377799 61.5793224 -r bilinear CanadaDemMosTuesdayClip.tif
CDem... Rick Reeves

04:02 PM Task #212: Validate fused DEM at SRTM/ASTER boundary

I am (finally) working through the 'image difference' analysis that Jim sketched out earlier this week.
And the firs... Rick Reeves

02:47 PM Task #212: Validate fused DEM at SRTM/ASTER boundary

Jim:
As I mentioned, after I completed my initial 'screen based' review of the boundary area, I intend to perform t... Rick Reeves

09:17 AM Task #212: Validate fused DEM at SRTM/ASTER boundary

A few comments:
Rick Reeves wrote:
> By superimposing the images and increasing the magnification
> on the lower le... Jim Regetz

11:05 AM Task #210: Produce global aspect layer

Take a look at the "@gdaldem@":http://www.gdal.org/gdaldem.html command-line utility. It includes an _aspect_ mode th... Jim Regetz

11:04 AM Task #209: Produce global slope layer

Take a look at the "@gdaldem@":http://www.gdal.org/gdaldem.html command-line utility. It includes a _slope_ mode that... Jim Regetz

04/28/2011

09:52 PM Task #212: Validate fused DEM at SRTM/ASTER boundary

Yes, the book IS the Wilson and Gallant book. This book is a decade old, and new techniques no doubt have been develo... Rick Reeves

01:25 PM Task #212: Validate fused DEM at SRTM/ASTER boundary

Presumably "the book" refers *Terrain Analysis* (2000) by Wilson and Gallant? Has the state of terrain analysis not ... Mark Schildhauer

11:26 AM Task #212: Validate fused DEM at SRTM/ASTER boundary

The book is on order, and should arrive at UCSB Library in 3 to 5 working days.
It will come in handy in several par... Rick Reeves

08:17 AM Task #212: Validate fused DEM at SRTM/ASTER boundary

Jim:
I think that Robert pointed me in the correct direction, but I took some steps to quantify the error and tes... Rick Reeves

04:33 PM Task #207: Produce global fused DEM layer

I have moved the "ReevesSpatialSoftwareStack.txt" file to the "Documents" section of Redmine, where it will be more o... Mark Schildhauer

07:46 AM Task #208: Evaluate existing E&O AML scripts

By May 4, I should have reviewed and tested the AML scripts that produce the terrain-derived data layers. In the abse... Rick Reeves

04/27/2011

11:23 PM Task #212: Validate fused DEM at SRTM/ASTER boundary

Rick -- I just noticed your "r-sig-geo":https://stat.ethz.ch/pipermail/r-sig-geo/2011-April/011578.html exchange with... Jim Regetz

10:42 PM Task #207: Produce global fused DEM layer

Mark, Jim, and I met today to review progress on the tasks related to Fused Terrain Layer construction
and to discus... Rick Reeves

10:14 PM Task #207: Produce global fused DEM layer

The first set of ASTER GDEM data search results for the Northern Hemisphere
that I downloaded using the NASA WIST d... Rick Reeves

04/26/2011

05:23 PM Task #212: Validate fused DEM at SRTM/ASTER boundary

Overlapping with Jim's notes (aboveon our discussions today:
I have created two images corresponding to southern ... Rick Reeves

05:20 PM Task #212: Validate fused DEM at SRTM/ASTER boundary

Rick -- this is a restatement of what I sketched out on the board earlier as one way of quantifying the boundary beha... Jim Regetz

04/22/2011

02:28 PM Task #215: Establish file organization and possible 'tiling' scheme for Fused Global Terrain data set

I propose dividing the globe into four quadrants:
Northwest Hemisphere, Southwest Hemisphere, Northeast Hemisphere,... Rick Reeves

02:20 PM Task #212 (In Progress): Validate fused DEM at SRTM/ASTER boundary

Rick Reeves

09:38 AM Task #212: Validate fused DEM at SRTM/ASTER boundary

I have assembled a good sample region, in Western British Colombia along the 60 degree latitude line
where SRTM and ... Rick Reeves

11:51 AM Task #208: Evaluate existing E&O AML scripts

Thank you Ming, more good information.
I do intend to assemble a workflow document of some type next week.
I will s... Rick Reeves

11:45 AM Task #208 (In Progress): Evaluate existing E&O AML scripts

I reviewed all of the AML scripts a second time and am ready to test them within ArcMap GIS. Next week I will do so r... Rick Reeves

04/21/2011

02:28 PM Task #212: Validate fused DEM at SRTM/ASTER boundary

As part of the fused digital terrain layer validation we are looking for 'edge discontinuities' at the boundary betwe... Rick Reeves

10:59 AM Task #207: Produce global fused DEM layer

I see your point re: cell resolution, if we stay in the realm of arc-seconds.
Yes, we are in agreement about produc... Rick Reeves

04/20/2011

04:05 PM Task #207: Produce global fused DEM layer

Also, when you're simply combining tiles, you can get big efficiency gains by using the VRT format with GDAL, rather ... Jim Regetz

03:48 PM Task #207: Produce global fused DEM layer

Thanks Rick. Regarding pixel sizes (cell resolution), what we've been calling "1km" is just shorthand for 30 arcsecon... Jim Regetz

02:10 PM Task #207: Produce global fused DEM layer

(continuing from previous update)
Digital Terrain File data sources:
CGIAR / SRTM 90 meter Digital Elevation Da... Rick Reeves

09:47 AM Task #207 (In Progress): Produce global fused DEM layer

Jim Regetz

09:43 AM Task #207: Produce global fused DEM layer

I have downlowded the complete set (872 files) of CGIAR / SRTM 90 meter data tiles and most if not all (2780) availa... Rick Reeves

04/19/2011

09:48 PM Task #212: Validate fused DEM at SRTM/ASTER boundary

Part of the process of constructing and testing the resampling/mosaicing scripts
for constructing the fused terrain... Rick Reeves

04/18/2011

01:36 PM Task #215 (Rejected): Establish file organization and possible 'tiling' scheme for Fused Global Terrain data set

The size and scope of the global fused DEM terrain layer makes it impractical
to distribute and use the layer (and ... Rick Reeves

01:12 PM Task #213 (Resolved): Confirm with Project Scientists: CGIAR Level 4 SRTM project supports planned Terrain Analysis

Review is complete, based on Rob G's response (below) and on
Based also upon discussions with Mark Sand Jim R on Apr... Rick Reeves

12:32 PM Task #208: Evaluate existing E&O AML scripts

Description of ten existing scripts (nine AML, one Python):
Aggregate.aml: Executes the aggregate (resampling) fun... Rick Reeves

04/15/2011

10:25 AM Task #213 (Resolved): Confirm with Project Scientists: CGIAR Level 4 SRTM project supports planned Terrain Analysis

Ming's initial research identified the SRTM Level 4 DEM data distributed by the CGIAR Consortium (http://srtm.csi.cgi... Rick Reeves

04/14/2011

03:42 PM Task #212 (Closed): Validate fused DEM at SRTM/ASTER boundary

Particularly for the purposes of examining and validating what happens at the SRTM/ASTER boundary, the fused DEM shou... Jim Regetz

02:21 PM Task #211 (New): Produce global flow accumulation layer

This will be based on the global DEM, but with processing possibly done at up to 90m resolution before aggregating to... Jim Regetz

02:15 PM Task #210 (New): Produce global aspect layer

This will be based on the global DEM, but with processing possibly done at up to 90m resolution before aggregating to... Jim Regetz

02:13 PM Task #209 (New): Produce global slope layer

This will be based on the global DEM, but with processing possibly done at up to 90m resolution before aggregating to... Jim Regetz

01:56 PM Task #208 (In Progress): Evaluate existing E&O AML scripts

There are 18 *.aml files in various parts of @eos:~organisms/topo@, although it looks like these are really 9 identic... Jim Regetz

11:50 AM Task #207 (In Progress): Produce global fused DEM layer

This is the top-level ticket associated with creation of a global fused DEM layer, with subtasks to flesh out specifi... Jim Regetz