David G. Long of www.mers.byu.edu

Remote sensing is the study of the environment from a distance. Recent developments in

satellite-based sensors and computer processing techniques offer unique perspectives of

our planet. Microwave remote sensing includes active (radars) and passive (radiometers)

sensors. This talk focuses on the applications of a class of active microwave remote

sensors known as scatterometers. Satellite scatterometers have been built and flown by

several nations including, the U.S., ESA, India, and China. Wind scatterometers are

satellite radars designed to measure near-surface vector winds over the ocean. The

scatterometer does not directly measure the wind. Rather, it measures the normalized

radar backscatter (so) of the surface. Then, from multiple so measurements, the wind

blowing over the ocean's surface is inferred. Scatterometer wind measurements have

wide application in air-sea interaction and weather observation. Wind scatterometers

typically operate at one of two bands, C (5.4 GHz) or Ku (13.4 GHz). Ku band is more

sensitive to wind, but also to the adverse effects of rain. However, this sensitivity can be

exploited to simultaneously estimate wind and rain.

Scatterometers also collect so measurements over land and ice. While the low resolution

(25 km) of the scatterometer measurements can limit their utility in land and ice studies,

reconstruction processing enables the generation of enhanced resolution so images from

past and present scatterometers. Such enhanced resolution scatterometer images have

been proven to be useful for high resolution wind/rain estimation as well as in a variety

of studies of polar ice and tropical vegetation. In particular enhanced resolution

scatterometer observations have been used over land to study deforestation of tropical

rain forest and desertification. Over the glaciated regions of Greenland and Antarctica,

the radar signal is very sensitive to melting conditions and can thus be used to global

warming conditions. The contrast between ocean and ice scattering enables tracking of

major Antarctic icebergs in all weather conditions. In this talk, a brief overview of

scatterometer remote sensing is provided and a number of applications of microwave

remote sensing are described.

 

Biography:

Dr. Long received the Ph.D. degree in Electrical Engineering from the University of

Southern California early in 1989 after previously receiving the B.S. and M.S. degrees in

Electrical Engineering at Brigham Young University in 1982 and 1983, respectively.

From 1983 through 1990 he was employed at NASA's Jet Propulsion Laboratory (JPL)

in the Radar Science and Engineering Section. He was responsible for the design and

development of the NASA Scatterometer (NSCAT) system to measure ocean surface

winds from space. NSCAT successfully flew aboard Japanese ADEOS spacecraft in

1996. He was a Group Leader in the Radar Systems Engineering Group at JPL were he

supervised work on the design and analysis of spaceborne scatterometer and SAR

systems including NSCAT, SIR-C, and Magellan. He was the original Experiment

Manager for SCANSCAT (now known as SeaWinds, it was first launched in 1999 on

QuikSCAT, again in 2003 on ADEOS-II, and again as RapidScat on the International

Space Station in 2014).

Since 1990 Dr. Long has been on the faculty of the Electrical and Computer Engineering

department (www.ee.byu.edu) at Brigham Young University (www.byu.edu). He is full

Professor who teaches radar, remote sensing, communications, and signal processing. He

is the Director of the BYU Center for Remote Sensing and Head of the Microwave Earth

Remote Sensing Laboratory (www.mers.byu.edu). Since 2012 has been an Associate

Dean of the Ira A. Fulton College of Engineering and Technology (www.et.byu.edu).

 

Email:

Address:Brigham Young University, 450 Engineering Building, Provo, Utah, United States, 84602