Remote Sensing - Lecture 1

Professor Menglin Susan JinSan Jose State University, Department of Meteorology

www.met.sjsu.edu/~jin

Outline of today’s lecture

1. Introduction and Welcome2. Discussion on the “Greensheet”3. Learning Contract4. First Glance on the Power of Remote Sensing from Space

For greensheet, class ppt notes

http://www.met.sjsu.edu/~jin/METR180.htm

About Professor

1.

2. to be an effective teacher

3.

A very good scholar www.met.sjsu.edu/~jin

Research projects: funded by NASA, NSF, Department of DefenseOn land surface climate change, urbanization, remote sensing

20 leading author papers on top journals

GoalMETO180 will help you to know the fundamentals of

Remote Sensing, Satellite Observations for Climate Change Research,

and gain appreciation of the complexities involved with climate change issues

Homework: 20%Midterm Exam(I and II): 30%

Class Participation 5%Research Project: 20%

Final Exam: 25%Scale: 90+ A, 80’s B, 70’s C, 60’s D, <60 F

Homework will be assigned in class collected in discussions on two weeks later.

Content

The structure of the course include:

Part 1: Basic theory

Part 2: Sensors and Image Processing

Part 3. Application in Climate Research.

See the greensheet for details

Why Remote Sensing

• Remote sensing systems are • Instructors area of research

• Wide area of interest with availability of sensor data (Google Earth)

• Examples in this course concentrate on terrestrial and atmosphere remote sensing

• The goal is not to teach remote sensing, but to familiarize with• Jargon/terminology from remote sensing • underlying physics

• Methods introduced here are used in a variety of other fields• Biomedical imaging• Astronomical studies• Industry and manufacturing• Each field has its own idiosyncrasies that will drive the

Strictly speaking, this course is designed to give anintroduction to the topic of remote sensing on earth system and climatology

Lecture Hour: 12:00 – 1:15AM, Monday and Wednesday

Place: DH615

Office Hour: Wednesday 1:30 -2:30 PM

Place: MSJ’s Office (DH621)

•I will meet with you for extra office hour whenever you need. •send email for appointment.

References (not a text book):

•Useful materials will be assigned on webpage/homework/class

Close-to-be TextbookSchott, J. R. 1997: Remote Sensing: The Image Chain Approach. Oxford University Press.

Reference BookKing, M. D. et al. 2007: Our Changing Planet: The View From Space. Cambridge; New York : Cambridge University Press,, 2007

•These two books are reserved for class reference in department library

Learning Contract

• Instructor– On time and prepared.– Answers questions.– Approachable and friendly.– Fair with assignments and grades.– Genuinely concerned about your learning and

intellectual development.

Learning Contract• Students

– Make every effort to arrive on time; and if late, enter class quietly.

– Preserve a good classroom learning environment by a) refraining from talking when other people

are talking b) turning off cell phones.

– Be courteous to other students and the instructor.– Aware that learning is primarily their responsibility.– Aware of universities policy on academic integrity

and pledge to abide by them at all times. – Have read and understand what plagiarism is and

know how to cite sources properly.

Academic Integrity• Integrity of university, its courses and

degrees relies on academic standards.• Cheating:

– Copying from another’s test, cheatsheet etc.– Sitting an exam by, or as, a surrogate.– Submitting work for another

• Plagiarism:– Representing the work of another as one’s own

(without giving appropriate credit)

Plagiarism• Judicial Affairs

http://sa.sjsu.edu/judicial_affairs/index.html

• Look at the Student Code of Conduct

• Read through SJSU library site on Plagiarismhttp://www.sjlibrary.org/services/literacy/info_comp/plagiarism.htm

• http://turnitin.com/

“Getting Acquainted" Quiz Class Participation

• Write three sentence about Quantum Physics• What is Electromagnetic Spectrum? • What are Transmittance, Absorptance, and

Reflectance?• Why do we need remote sensing from space?• What are the advantages of remote sensing

technique, you feel?• What are the disadvantages of remote

sensing, you feel?

Let’s see

Remote Sensing: Needs and Examples

.

.

1. Why do we need remote sensing from space?

2. What are the advantages of remote sensing technique?

3. What are the disadvantages of remote sensing?

MODIS Snow Observations

Advantages of MODIS snow (pervious video)

• High resolution (1km)

• High Coverage (global)

• Can assess remote regions including mountains and polar regions

• Continuous observations (2-per-day, 10 years)

Fire Observation on Mountain EtnaIn July 2001 Mt Etna on the island of Sicily exploded dramatically into life.

Himalayas

Land cover,

Elevation

Surface roughness

Snow coverage

Surface temperature

Vegetation

albedo

SST

SST_Q01

Clouds and Aerosol

video: Aerosol-GRECE_1

Concept of Remote Sensing

“Remote sensing” is something we do all the time!

Several of the human senses gather their awareness of the external world almost entirely by perceiving a variety of signals, either emitted or reflected, actively or passively, from objects that transmit this information in waves or pulses.

One World

A formal and comprehensive definition of applied remote sensing• Remote Sensing in the most generally accepted meaning refers

to instrument-based techniques employed in the acquisition and measurement of spatially organized (most commonly, geographically distributed) data/information on some property(ies) (spectral; spatial; physical) of an array of target points (pixels) within the sensed scene that correspond to features, objects, and materials, doing this by applying one or more recording devices not in physical, intimate contact with the item(s) under surveillance (thus at a finite distance from the observed target, in which the spatial arrangement is preserved); techniques involve amassing knowledge pertinent to the sensed scene (target) by utilizing electromagnetic radiation, force fields, or acoustic energy sensed by recording cameras, radiometers and scanners, lasers, radio frequency receivers, radar systems, sonar, thermal devices, sound detectors, seismographs, magnetometers, gravimeters, scintillometers, and other instruments.

This is a rather lengthy and all-inclusive definition

make a list of key words in it

• Acquisition/measurement; • data/information; • properties; • phenomenon,...• material; • recording device; • not in contact; • measuring field;• radiation; • instruments.

two more simplified definitions

• First:Remote Sensing involves gathering data and information about the physical "world" by detecting and measuring signals composed of radiation, particles, and fields emanating from objects located beyond the immediate vicinity of the sensor device(s)

• Second:

two more simplified definitions

• Second: (more related to this course)

Remote Sensing is a technology for sampling electromagnetic radiation to acquire and interpret non-contiguous geospatial data from which to extract information about features, objects, and classes on the Earth's land surface, oceans, and atmosphere (and, where applicable, on the exteriors of other bodies in the solar system, or, in the broadest framework, celestial bodies such as stars and galaxies).

This diagram for remote sensing

Key components of Remote Sensing

• Sensor

• Object (not contiguous to sensor)

• Radiation (shortwave, infrsred, microwave etc)

• Things emits energy (sun, earth surface etc)

Atmospheric Properties vs. Altitude

Atmospheric Pressure with Altitude

Pressure in the Atmosphere

•Atmospheric pressure can be imagined as the weight of the overlying column of air. •pressure decreases exponentially with altitude.

•but 80 percent of the atmosphere’s mass is contained within the 18 km closest to the surface.

•measured in millibars (mb)

•At sea level, pressure ranges from about 960 to 1,050 mb, with an average of 1,013 mb.

Vertical Layers of the Lower Atmosphere

The Height of Satellite OrbitMODIS (polar-orbit): 705kmGOES (geosynchronous): 36,000km

At a height of 200 mi (320 km), the period of a circular orbit is 90 min; at 500 mi (800 km), it increases to 100 min. At a height of 22,300 mi (36,000 km), a satellite has a period of exactly 24 hr, the time it takes the earth to rotate once on its axis; such an orbit is called geosynchronous

See handout to calculate the period of orbit

Why need remote sensing in climate change study?

Change in surface temperature in 20th century

Temperature is measured by therometer

World Meteorological Organization (WMO) http://www.wmo.int/pages/index_en.html

Weather station

http://www.nationmaster.com/encyclopedia/Image:Translational-motion.gif

The Land and Oceans have both warmed, but…

Precipitation patterns have changed

1. Evaporation, transpiration (plants)

2. Atmospheric transport (vapor)

3. Condensation (liquid water, ice)

4. Precipitation

5. Surface transport (continental rivers, aquifers and ocean currents)

Earth’s Hydrological Cycle - Schematic

PHYS 622 - Clouds, spring ‘04, lect. 1, Platnick

Why need remote sensing in climate change study?

• Satellite Data can provide additional information at high resolution, global coverage and long duration to study climate and climate change.

About Research Project

• Paper review on sensor/variable you choose:MODIS clouds

MODIS aerosolMODIS land skin temperatureMODIS albedoMODIS water vaporTRMM rainfallOMI Ozone

. Analyze the data using online visualization tool