Buoy retrieved for winter

Special thanks to Chris Pedergast and Clint Streeter from ESSP and Steve and Mike from Lake Region Water Rescue team, who helped to get the buoy back before the lake freezes. It was a perfect day, calm with mild temperature (about 2 Deg C, but this is November in North Dakota). It was the first time for me to sit on an air-boat. It was noisy, but it was easy to reach out.

The buoy was quite dirty with bio-fouling. We will need to clean it. Also, I need to send the GPS unit for calibration. The recorded elevation changes were too high, about 10 m daily.

Buoy launched to the Stump Lake

The buoy was officially launched to the Stump Lake at 2:40 pm today. With the help from Kate Overmoe, Chris Pendergast, and John Nelson (the boat person), the launch went smooth and measurements started immediately. Here are a few pictures

Buoy in Devils Lake

Did a site evaluation at the Stump Lake on Aug. 25, 2011. Will deploy the buoy at the Stump Lake, where the natural outlet of the Devils Lake, Tolna Coulee, starts and flows to the Cheyenne River.

Welcome Ms. Jiexia Wu

Ms. Jiexia Wu from China joined our program on Aug. 11, 2011.

NDSU field experiment finished on 06/30/2011

The NDSU field experiment finished on 06/30/2011. The project, funded by a NASA EPSCoR grant, was to measure the sensible and latent heat fluxes.

Three students were accepted into M.S. program

Three students were accepted into M.S. program, Mr. Anparasan Mahalingam, Ms. Jiexia Wu and Mr. Yilun Shao. I'm excited of meeting them soon.

a paper accepted for Geocarto International

Xiaodong Zhang, Hojin Kim, Clinton Streeter, David Claypool, Ramesh Sivanpillai, and Santhosh Seelan, Near Real-Time High Resolution Airborne Camera for Precision Agriculture, was accepted for publication in Geocarto International.

buoy in Devils Lake

We will deploy a buoy in Devils Lake to monitor water quality. Haven't decided where to put, but Stump Lake sounds like a good location given recent appeals for Tolna coulee outlet. The water in Stump Lake is very saline, with values significantly higher than the surrounding water bodies.

a paper submitted to Soil Science Society of Americ Journal

'Estimating surface soil moisture in the Red River Valley of the North Basin using Landsat 5 TM data' by Santosh Rijal, Xiaodong Zhang and Xinhua Jia was submitted to Soil Science Society of America Journal for review.

a paper submitted to JGR-Ocean

"The optical volume scattering function in a surf zone inverted to derive sediment and bubble particle subpopulations" by Michael Twardowski, Xiaodong Zhang , Svein Vagle , James Sullivan , Scott Freeman , Helen Czerski , Yu You , Lei Bi , and George Kattawar was submitted to JGR for review.

Realign SLS20 after storm

A severe storm on May 30 blew the SLS20 receiver down to ground. Realigned the SLS20 on Jun 1. It went well, except initially the signal lever were too strong. However, the automatic background calibration cannot be used - the outputs would be zeros. Also checked the batteries.

a paper submitted to IEEE Transactions on Geosciences and Remote Sensing

Geolocation algorithm for payload system onboard International Space Station, by Changyong Dou, Xiaodong Zhang, Hojin Kim and Huadong Guo, was submitted to IEEE Trans. Geosci. Remote Sensing

Kate passed comprehensive examination

Congratulations to Kate, who passed the comprehensive examination today.

Field experiment went well

The experiment with SLS20 and OEBMS-1 went smoother than I had expected, mostly thank to the help from Xinhua, Junyu, Santosh, Ishara and Daniel. The alignment of SLS20 went very well, again better than last time when the instrument was tested. Still, an automatic alignment will be helpful. Installation of OEBMS-1 went well. There are three dangling connections from soil heat flux sensors that we did know where to connect. But it seems the system works.

We tried to power the SLS20 transmitter and receiver with one battery, but it did not work. Tried to connect two batteries in serial mode to boost the output voltage to 24 V, but it did  not solve the problem. Hope Daniel will find out the reason.

It was a sunny day and we all got Sun burn. At least it was not cold.

Congratulations on graduation of Santosh and Junyu

Santosh Rija and Junyu Yang graduated on May 14, 2011. I would like to attend their commencement ceremony, but I had to go to the field to set up the experiment. Congratulations on both of them. They started their study here in the Fall of 2008. Santosh will go to Southern Illinois University at Carbondale for Ph. D study at Department of Geography and Junyu is looking to advance his career in business administration. Wish them nothing by success.

Field experiment at North Dakota State University campus

We will set up an OEBMS-1 (Optical Energy Balance Measurement System) at the NDSU campus during the weekend of May 14 and 15. The OEBMS-a consists of The OEBMS1 consists of one SLS20 scintillometer system with tripods to measure the sensible heat flux, one pyrradiometer (0.3 – 30 μm) and one pyranometer (0.3 – 3 μm) to measure the radiation flux balance and three soil heat flux sensors. The latent heat flux is calculated as residuum of the other components. Two ventilated thermometers Pt1000 and one pressure sensor provide the auxiliary data for an automatic derivation of the turbulent heat flux from the scintillation measurements. The Signal Processing Unit interfaces with all sensors and communicates with a PC via a RS232 link. The software outputs the turbulent fluxes of sensible and latent heat, the incoming solar and net radiation and the ground.


It was raining on may 14. Will work tomorrow.

Workshop on modeling of Devils Lake flooding

We will have a workshop on modeling and prediction of Devils Lake flooding on May 5 (Thursday) starting 1:00 pm in the room CH 368 (the class room). The workshop include individual presentations and group discussion. The speakers include USGS scientists, Dr. Skip Vecchia and Dr. Gregg Wiche, UND/Civil Engineering Dr. Howe Lim, UND/ESSP  Dr. Andrei Kirilenko and Mr. Dave Barta. The meeting is open to anybody who is interested and if this meeting may be of interest to someone you know, please invite them.

Here is tentative agenda.

Xiaodong: introduction of speakers and purpose of the workshop
Gregg: the background on the history of flooding in Devils Lake and the Red River
Skip: the USGS Devils Lake stochastic simulation model with implications for climate change and/or variability
Lim: using U.S. Army Corps of Engineering's HEC HMS and HEC ResSim models to simulate Devils Lake's hydrological process
Andrei: climate change and its effect on Devils Lake flooding
Dave: Economic analysis on Devils Lake mitigation projects
Group discussion

Again everybody is welcomed and refreshment will be provided.

34th ISRSE in Sydney

Presented "Web-based near real-time remote sensing data system providing decision support for precision agriculture" on April 14 (Thursday).

Manuscripts submitted for review

H. Czerski, M. Twardowski, X. Zhang, and S. Vagle, Resolving size distributions of bubbles with radii less than 30 microns with optical and acoustical methods, was submitted to Journal of Geophysical Research

Xiaodong Zhang, Hojin Kim, Clinton Streeter, Dave Claypool, Ramesh Sivanpillai,  and Santhosh Seelan, Near Real-Time Meter-Resolution Airborne Imagery for Precision Agriculture: AEROCam, was submitted to GeoCarto International

Catch-up of earlier events

2011-03-01: Kate Overmoe Kenninger was awarded a North Dakota Water Resource Research Institute Fellowship for her study of Assessment of Water Quality in Devils Lake using Satellite Imagery.

2011-02-02: Junyu Yang successfully passed his M.S. Thesis Defense: Remote Sensing Methods of Energy Fluxes Measurements: Intercomparison between SEBAL, Scintillometer and Eddy-covariance measurements and Landsat Images.

2011-01-24: "Retrieving Composition and Sizes of Oceanic Particle Subpopulations from the Volume Scattering Function" by Xiaodong Zhang, Michael Twardowski and Marlon Lewis is accepted for publication in Applied Optics.

2010-11-29: Santosh Rijal successfully passed his M.S. Thesis Defense: Developing a remote sensing algorithm for deriving soil moisture concentration from spectral reflectance

First blog

I can no longer ignore or resist using blog any more. This will serve as an update on the academic and research activities that are constantly evolving in my group. I will update the site as often as possible.