METR155 Remote Sensing - Lecture 1
Professor Menglin Susan Jin
San Jose State University, Department of Meteorology and Climate Science
Class notes- www.met.sjsu.edu/~jin
Outline of today’s lecture
1. Introduction and Welcome
2. Discussion on the “Greensheet” – overview of this class
3. Learning Contract
4. First Glance on the Power of Remote Sensing from Space
5. Get-to-know each other exam
For greensheet, class ppt notes
http://www.met.sjsu.edu/~jin/METR155fall2012.htm
About Professor
1.
A very good scholar www.met.sjsu.edu/~jin
Research projects: funded by NASA, NSF, Department of Defens
On land surface climate change, urbanization, remote sensing
20 leading author papers on top journals
2.
an effective teacher
3. Approachable,
4. Respectful
5. Encouraging
Goal
METR155 will help you to know
the Fundamentals of Remote Sensing,
Satellite Observations for Climate Change Research,
and gain appreciation of the complexities involved with remote sensing
For METR155 Students
Homework: 30% (10-12 homework)
Midterm Exam(I and II): 40%
Class Participation 5%
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 about 1-2 weeks later.
Fore METR280 Students (graduate students)
Homework: 25% (10-12 homework)
Midterm Exam(I and II): 30%
Class Participation 5%
Research Project 20%
Final Exam: 20%
Scale: 105+ A, 90’s B, 78’s C, 65’s D, <65 F
Homework will be assigned in class
collected in discussions on 1-2 weeks later.
Content
The structure of the course include:
Part 1: Basic theory –radiation, sensor design, orbit
Mid-term1
Part 2: Image Processing and Retrieval
Skin Temperature,
Vegetation Index
Cloud Effective radius
Research project
Mid-term2
Part 3. Application in Climate Research.
Research Report
Final Exam
See the greensheet for details
Lecture Hour:
10:30 – 11:45 PM, Tuesday and Thursday
Place:
DH615
Office Hour: Wednesday 11:00 AM -12:00 PM
Tuesday 1:15-2:15 PM
Place: MSJ’s Office (DH613)
TA: TBD
•I will meet with you for extra office hour whenever you need.
•send email for appointment.
References:
Close-to-be Textbook
King, M. D. et al. 2007: Our Changing Planet: The View From Space.
Cambridge; New York : Cambridge University Press,, 2007
Reference Book
Stephens, G. L. “Remote Sensing of the Lower Atmosphere: An Introduction”
Schowengerdt, Robert A.: Remote Sensing Models and Methods for
Image Processing (2nd edition). Academic Press.
Schott, J. R. 1997: Remote Sensing: The Image Chain Approach.
Oxford University Press.
•Useful materials will be assigned on webpage/homework/class
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 your 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
Plagiarism
http://www.sjlibrary.org/services/literacy/info_comp/plagiarism
.htm
One World
Why Remote Sensing
Strictly speaking, this course is designed to give an
introduction to the topic of remote sensing on earth system and climatology
• 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
“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?
“Getting Acquainted" Quiz
answers
Write three sentence about Quantum Physics
Quantum physics is a branch of science that deals with discrete, indivisible
units of energy called quanta as described by the Quantum Theory.
There are five main ideas represented in Quantum Theory:
•
Energy is not continuous, but comes in small but discrete units.
•
The elementary particles behave both like particles and like waves.
•
4. The movement of these particles is inherently random.
•
It is physically impossible to know both the position and the momentum of
a particle at the same time. The more precisely one is known, the less
precise the measurement of the other is.
•
The atomic world is nothing like the world we live in.
(courtesy http://library.thinkquest.org/3487/qp.html)
“Getting Acquainted" Quiz
answers
•
Write three sentence about Quantum Physics
Quantum physics is a branch of science that deals with discrete, indivisible units of energy called
quanta as described by the Quantum Theory. There are five main ideas represented in
Quantum Theory:
•
Energy is not continuous, but comes in small but discrete units. 1
•
The elementary particles behave both like particles and like waves. 2
•
The movement of these particles is inherently random. 3
•
It is physically impossible to know both the position and the momentum of a particle at the
same time. The more precisely one is known, the less precise the measurement of the other
is.4
•
The atomic world is nothing like the world we live in. 5
•
•
•
•
•
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?
“Getting Acquainted" Quiz
answers
•
What is Electromagnetic Spectrum?
The electromagnetic spectrum is the range of all possible
frequencies of electromagnetic radiation
•
What are Transmittance, Absorptance, and Reflectance?
•
Why do we need remote sensing from space?
•
What are the advantages of remote sensing technique, you feel?
Large coverage, long-duration, many variables observed
instantaneously, etc
•
What are the disadvantages of remote sensing, you feel?
Uncertainties remain. For example,
clouds/aerosol/atmosphere interruption, surface noise, instrument
design not perfect, retrieval algorithm needs development, etc
More on Quiz
• To ensure the good communication
between professor and students, how
would you feel that the professor is
approachable?
• After each class, how many hours do you
to spend to go over class material?
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
See this video at http://www.met.sjsu.edu/~jin/video/GlobalSnow.mpg
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 Etna
In July 2001 Mt Etna on the island of Sicily exploded dramatically into life.
See this video at http://www.met.sjsu.edu/~jin/video/MtEtna.mpg
Himalayas
Land cover,
Elevation
Surface roughness
Snow coverage
Surface temperature
Vegetation
albedo
See this video at
http://www.met.sjsu.edu/~jin/video/Himalayas.mov
Katrina
See this video at http://www.met.sjsu.edu/~jin/video/katrina-visir_sm.mov
Clouds and Aerosol
video: Aerosol-GRECE_1
See this video at http://www.met.sjsu.edu/~jin/video/aerosol-GRECE_1.mov
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).
Vertical Layers of the Lower Atmosphere
Atmospheric Properties vs. Altitude
This diagram for remote sensing
Radiation, EM specturm
Orbit platform
• Electromagnetic radiation behaves in most
circumstances as waves and can thus be
characterized as waves.
• See
http://users.humboldt.edu/rpaselk/C107.F09/C107Notes/C107nLec1
3.html
• Labeled sine wave diagram
thermal radiation
• All matter above absolute zero
(0 Kelvin = -273°C = - 459.4°F)
emits radiant energy in form of
electromagnetic waves.
• The basic physical law
concerning thermal radiation
emission is the Stefan
Boltzmann law, which states
that that the heat flux emitted
by an ideal radiator which is
called a blackbody is
proportional to the absolute
temperature (in K) to the
fourth power
•
3 key three additional properties of surfaces which control the radiation heat transfer
of a surface - The absorptivity α, transmissivity T and the reflectivity ρ.
thermal radiation (cont.)
• Real surfaces emit less
radiation than the ideal
blackbody. The ratio of
actual emissive power Eb
to the emissive power of
a blackbody Eb at the
same temperature is
called the emissivity.
• Furthermore Kirchhoff’s
identity rule states that
absorbtivity and
emissivity are equal at
the same wavelength.
aλ=ελ
Besides the sun, al other objects with temperature > 0 K emits radiation
at their temperatures
Key components of Remote
Sensing
• Sensor
• Object (not contiguous to sensor)
• Radiation (shortwave, infrared, microwave
etc)
• Things emits energy (sun, earth surface
etc)
Class activity
•
•
Is there remote sensing here?
Explain in terms of major components
emitted or reflected,
actively or passively,
• Senor senses radiance either emitted
(from earth surface, atmosphere) or
reflected solar radiation
• Sensor can either passively receive
radiance from the object or emit radiance
to the object first and then receive its
reflected signal
Example of passive and active
remote sensing
In this figure, which is passive and which is active remote sensing environment
Passive and Active Remote
Sensors
• Remote sensing systems which measure energy
that is naturally available are called Passive
Sensors. (Sun, surface emission, etc)
• Active sensors, on the other hand, transmit
short bursts or 'pulses' of electromagnetic
energy in the direction of interest and record the
origin and strength of the backscatter received
from objects within the system's field of view.
Passive systems sense low level microwave
radiation given off by all objects in the natural
environment.
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…
Earth’s Hydrological Cycle - Schematic
1.
Evaporation, transpiration
(plants)
2.
Atmospheric transport
(vapor)
3.
Condensation (liquid water,
ice)
4.
Precipitation
5.
Surface transport
(continental rivers, aquifers
and ocean currents)
PHYS 622 - Clouds, spring ‘04, lect. 1, Platnick
Precipitation patterns have
changed
Importance of remote sensing
Remote Sensing allows data in locations that may be
inaccessible or too large for in situ approaches
• Interplanetary studies are an excellent example of where remote
sensing is useful
• Sample and return missions are expensive and difficult
• Apollo missions were last fully successful sample and return missions
(Genesis was partially successful)
• Still, remote sensing was critical even in those missions to determine
where best to sample
Meteorological applications
• Probably the clearest example with the widest audience and daily impact
• Meteorological satellites cover large areas that are inaccessible
• Can cover these areas repeatedly to look for changes over time
• National Defense
• Resource Mapping
“Getting Acquainted" Quiz
answers
•
Write three sentence about Quantum Physics
Quantum physics is a branch of science that deals with discrete, indivisible units of energy called
quanta as described by the Quantum Theory. There are five main ideas represented in
Quantum Theory:
•
Energy is not continuous, but comes in small but discrete units. 1
•
The elementary particles behave both like particles and like waves. 2
•
The movement of these particles is inherently random. 3
•
It is physically impossible to know both the position and the momentum of a particle at the
same time. The more precisely one is known, the less precise the measurement of the other
is.4
•
The atomic world is nothing like the world we live in. 5
•
•
•
•
•
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?