Agronomy / Electrical Engineering / Meteorology 518 Microwave Remote Sensing Syllabus for Spring 2012 (Next offered Spring 2014, Spring 2016, ...) Tues/Thurs 11-12:30 1246 Howe Hall Professor Brian Hornbuckle 3007 Agronomy Hall bkh@iastate.edu

Course Summary

Catalog description: Microwave remote sensing of Earth's surface and atmosphere using satellite and ground-based instruments. Specific examples include remote sensing of atmospheric temperature and water vapor, precipitation, ocean salinity, and soil moisture.

Objectives: Understand the physical principles of microwave remote sensing; describe the models that represent these physical principles; and use these models to make quantitative predictions.

Prerequisites: Math 265 or equivalent (third semester calculus, three-dimensional calculus). Good physical science background. Some computer programming experience at an introductory level (no particular language).

Text: I submitted an order for a textbook, Microwave Remote Sensing: Active and Passive, Volume 1 Fundamentals and Radiometry (Ulaby, Moore, and Fung) but the order was lost by one of our academic departments. I'm working with the University Bookstore now to get the text as soon as possible. Along with this book there are three others on reserve (or soon to be on reserve) at the library: Fundamentals of Applied Electromagnetics (F. T. Ulaby), Introduction to the Physics and Techniques of Remote Sensing (Van Zyl and Elachi); and Absorption and Scattering of Light by Small Particles (Bohren and Huffman). The Ulaby book is what I used to study for my qualification exam in electrical engineering and should be helpful if more information is needed in the first section of the course (the fundamentals). There are other similar books: one by Cheng, and whatever is being used to teach E E 311. The Van Zyl and Elachi book is much more recent than our class text (which I will usually refer to as UMF for Ulaby, Moore, and Fung) but the perspective is different from mine (which may be good for you) since I learned the material using UMF. The Bohren and Huffman book has one nice section on the big-picture of scattering, and I hope to use another section if we have time near the end of the course.

Topics: Overview of relevant electromagnetic theory and antenna theory, including Maxwell's equations, the wave equation, plane wave propagation, propagation in a lossy medium, polarization, Fresnel refection and transmission, Snell's law, the short dipole, antenna pattern, beam dimesions, directivity, and gain. Radio science, including the energy and power density of radiation, thermal equilibrium, Planck radiance, the Stefan-Boltzmann law, grey body radiance, the Rayleigh-Jeans law, constitutive properties of natural media, the radiative transfer equation, Kirchoff's law of thermal radiation, and scattering by small particles. At the end of the course a brief overview of active sensing, including the radar equation, will be given to contrast with the material on radiometry. Applications include atmospheric sounding, remote sensing of precipitation, and remote sensing of Earth's surface.

We will use the following satellite missions as current examples of microwave remote sensing: TRMM, Aqua, SMOS, Aquarius, and SMAP. Occasionally there are relevant images from NASA's Earth Observatory site, although the majority of these images are visible/infrared and not microwave (but still fun to look at!).

Learning Experiences: Lecture and discussion, problem sets, and a semester lab/project. During the first half of the course, problem sets are assigned every Tuesday and due the following Tuesday at the beginning of class. The first half is focused on the physical basis of remote sensing. We will often use computer simulations from Physics Education Technology (PHET) to play and experiment with basic physical concepts. In the second half, there are fewer problem sets but they are longer and focused on specific applications of microwave remote sensing.

In addition to quantitative problem solving, each problem set also requires you to read material on current events in remote sensing. Some of the current event articles will be found using their digital object identifier (DOI). To find the article, enter its DOI at http://dx.doi.org. For example, if the DOI is "doi:10.1016/j.agrformet.2008.07.002" then paste "10.1016/j.agrformet.2008.07.002" (leave out the "doi:") into the box and click "Go." If you are on the ISU campus you should be able to immediately access the article. If you are using a computer off campus, you will have to login to the ISU library since ISU pays for the electronic subscriptions to these magazines and journals.

You are strongly encouraged to use MATLAB software to numerically solve and graph problems. MATLAB is a powerful and easy-to-use programming environment that provides many functions that simplify programming and particularly the creation of good-looking figures. I will often supply example code and functions written in MATLAB. Some of the assignments will require the use of MATLAB. MATLAB is available on all of the machines in Agronomy Hall 3128, and in many other locations across campus, particularly in the College of Engineering. MATLAB is also available free of charge to all ISU students (see ISU IT services, "IT for You, Students, Software (Downloads), Licensed Software" then search for "matlab"). Other software packages may be used if assignments can be completed fully. All code (and especially code not written in MATLAB) must be well documented with comments if you would like to be awarded partial credit. New this year! It may be to your advantage (particularly if you are a meteorology student) to learn python instead of MATLAB. Jason Patton, a graduate student in agricultural meteorology, will be a resource for python use and will translate my MATLAB code into python code.

Exams: There are two exams: a mid-term exam on March 6 over the first half of the course; and a final exam on May 5 over the material covered since the mid-term exam. For each exam please bring a two-page (front and back of a single page) summary of the relevant material (a different summary sheet for each exam), including equations, conceptual information, etc. You will use this material to help you complete the test. You do not need to include the values of constants or material properites (e.g. the Stefan-Boltzmann constant, etc.). The only other materials you will be allowed to use on the exams are a calculator and a pen (not pencil). I am asking you to develop this summary sheet for three reasons: for your use on the exams; as a method of studying for the exam; and concise record of the important topics in the course that you will be able to refer to after the course has been completed.

Semester Laboratory / Project: The semester project will be a comprehensive laboratory report. The laboratory will consist of using my research group's L-band microwave radiometer to observe both the sky and the ground. The data reported by the radiometer will then be compared with model results produced by using in-situ measurements of the atmosphere and Earth's surface. The report is due by noon, Tuesday, May 4.

Grading: I will assign a letter grade for the course at the end of the semester based on a numerical score that is composed of the following: 25% problem sets, 25% semester project, 25% mid-term examination, 25% final examination. Current grade records are here.

Office Hours: Official office hours will be from 2-4pm on Mondays since the problem sets are normally due on Tuesdays. You are welcome to come talk to me when you see the door to my office open. In rare cases, I may ask you to come back at another time. It is best to contact me by email and set an appointment time if you have a lengthy question. Please do not stop by Tuesday and Thursday mornings as I am usually busy preparing for class.

Special Needs: Please address any special needs or special accommodations with me at the beginning of the semester or as soon as you become aware. Those seeking accommodations based on disabilities should obtain a Student Academic Accommodation Request (SAAR) from the Disability Resources office (515-294-7220), located in Room 1076 of the Student Services Building.

Schedule of Topics