Archive for June, 2012

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Soil Moisture Active Passive (SMAP): Crop Structure Sampling

June 18th, 2012 by Brian Campbell

Narendra Das
Jet Propulsion Laboratory

 

During the SMAPVEX12 campaign measurements are being made simultaneously by airborne remote sensing instruments (PALS and UAVSAR) and by in situ sampling of the field sites. Measurements of the vegetation/crop structure characteristics and attributes during the vegetation growth phases are an important part of the data collection.

Crop structure measurements collected during the campaign will be used to calibrate and validate (cal/val) the SMAP radar forward models (radar backscatter is highly sensitive to vegetation structure). For this purpose most of the landcover types available in the SMAPVEX12 study domain are being sampled to obtain vegetation/crop structure information.

Fig 1. Canola field-124, Date: 06-07-2012.

 

Fig 2. Canola field-124, Date: 06-16-2012

For more information. visit the SMAP Blogs from the Field site.

Soil Moisture Active Passive (SMAP): Forest Sampling

June 17th, 2012 by Brian Campbell

Parag Narvekar. Massachusetts Institute of Technology

 

Aspen trees (deciduous forest) comprise more than 90% of the sampled SMAPVEX12 forest sites, with an understory layer of shrubs and grass. The dense shrubs make it difficult to access the sites, therefore the soil moisture and vegetation sampling schemes adopted for these sites are different from the cropland sites. A representative circular area of 200 meter diameter is selected for each forest site and within this area intensive ground measurements of soil moisture and vegetation are made.

Even though my research is not directly associated with forested areas it was great to visit these sites along with other team members and get experience of actual conditions, from which to derive the scientific basis for emission and scattering mechanisms responsible for active and passive signals captured by the PALS airborne instrument (and later SMAP).

Diagram and photos of forest vegetation.

 

To read more, visit the SMAP Blogs from the Field site.

Soil Moisture Active Passive (SMAP): On the Twin Otter

June 16th, 2012 by Brian Campbell

Andreas Colliander
Jet Propulsion Laboratory

On the second science data acquisition flight of PALS (on June 12) I got to fly on board the Twin Otter aircraft for the flight segment after the mid-day refueling stop at Winnipeg airport. Due to the minimal requirement for a second PALS operator on this flight I took Ian’s place on the plane while Seth continued to be in charge of the PALS instrument operation.

The day was beautiful, the skies mostly clear and the ride very smooth (the going can easily get bumpy on a small plane like the Twin Otter) at about 8500 ft altitude as planned for this flight.

Forest and pasture region at the northern end of the experiment area.

 

Bubble windows allow an extra-aircraft perspective and a look straight down

 

To read more and see more images, visit the SMAP Blogs from the Field site.

Soil Moisture Active Passive (SMAP): Clear Skies & Forest Sites

June 15th, 2012 by Brian Campbell

Eni Njoku
Jet Propulsion Laboratory
Mariko Burgin
University of Michigan

Today the skies are clear. PALS is flying again today, and also flew on June 12th. So this is the third PALS flight day. There is hardly a cloud in sight anywhere as PALS takes off. The soil moisture sampling crews are out.

Location of the forest sites (red) and cropland fields (blue) where access for sampling was granted. Fields where the AAFC long term in situ stations are installed are identified in orange.

 

Pasture just outside F2 has to be crossed to enter the site. Approximate distance from car to entrance of site is about 300 meters (Day 1: 6/7/2012).

 

F2 S1: Mariko at easternmost point. Very clay-rich soil in marshy vegetation (6/7/2012).

 

To read more and see more images, visit the SMAP Blogs from the Field site.

Soil Moisture Active Passive (SMAP): Notes From the Field

June 14th, 2012 by Brian Campbell

Grant Wiseman
Agriculture and Agri-Food Canada

After much preparation and anticipation it is hard to believe the first week of the SMAPVEX12 campaign is already behind us. The week began with a successful training session held at the Regional Operation Centre (ROC) in Winnipeg. Field teams were instructed on how to use Hydra Probes, CropScan Cameras and Surface Roughness Profilers among other data collection instruments.

The first field sampling day went extremely smooth…

Read more at the SMAP Blogs from the Field site.