The presentation introduces remote sensing technology and how it is used in studying atmospheric aerosols. Remote Sensing technology uses the optical property of aerosols to detect the presence and the type of aerosol. The type or the characteristics of an aerosol is determined by seven factors which are interpreted from the satellite image. The satellite image is retrieved from geosynchronous and polar satellites, of which the latter is preferred for aerosol applications.
In addition, features and terminologies associated with remote sensing, satellite and aerosol optical properties are discussed. This project emphasizes on an interactive material that is best supplemented with lecture video. It is not designed to be conventional lecture slide. Point to note: the question mark appearing in bottom of the slides indicates the author raised a question during the lecture.
This presentation was delivered in coming-of-age lecture style, in contrast to old-school conventional style. This presentation stimulates audiences to think and act than a banal display of abstract data. The lecture videos can be found at:
[1] Part-1/2 (52 minutes): https://youtu.be/-O_mYoeg-us
[2] Part-2/2 (51 minutes): https://youtu.be/IhHHHZYcY0o
This presentation is done as a part of graduate course titled Aerosol Mechanics in Spring 2016. The author was pursuing MS in Environmental Engineering Sciences at University of Florida during the making of this project.
4. Two Areas
remote sensing
technology to capture
optical wave changes
satellite - sensors
aerosol technology
deducing true form from remote
sensing inputs
optical properties
6. What is Remote Sensing?
Science of acquiring information about an object
without having a physical contact.
7. Terminology
“Science – and the art – of
identifying, observing, and measuring an object
without coming into direct contact with it.”
Ms. Evelyn Pruitt
US Office of Naval Research
1950’s
Source: Earth Observatory, National Aeronautics and Space Administration
8. What others say?
“acquisition of information about an object or phenomenon without making physical
contact with object.. thus in contrast to site observation”
“..in modern usage.. use of aerial sensor technologies to detect and classify objects on
earth.. surface, atmosphere, oceans.. by means of propagated signals on earth”
– Wikipedia (Feb 2016)
“collecting and interpreting information about the environment and the surface.. from a
distance.. primarily by sensing radiation that is naturally emitted or reflected.. by sensing
signals transmitted from a device and reflected back to it.”
– Environmental Systems Research Institute (Feb 2016)
13. Types (source)
based on light source,
passive active
external source self source
(sun, earth) (electromagnetic pulse)
eg. Landsat, ASTER, AVHRR eg. LIDAR, RADAR, SONAR
not only visible
14. Types (orbit)
based on orbit,
geo-synchronous polar
orbital period 24h orbital period <2h
high altitude (~36000 km) low altitude (700 - 800 km)
same location all time weather forecast, landuse,
communication sea-surface temperature
http://scijinks.jpl.nasa.gov/orbit/
20. Why remote sensing?
inaccessible locations by ground transport
continuous monitoring and observation
non-destructive observation (no physical contact)
macroscale observations (national-scale and continent-scale)
observations less affected by weather catastrophes
high precision (no bias or manipulation)
energy efficient (sourced by solar energy)
versatility (one device, many applications)
longer life (no wear/tear)
less maintenance issues
30. Applications
air quality
road networks and urbanization
meteorology
disaster management
aerosol source regions
global transport patterns
agriculture crop yield, land use management
ocean and land surface characteristics
national security
explore terrestrial bodies
astronomy and cosmology applications
33. Organizations
founded
NASA National Aeronautics and Space Administration 1958
IKI RAN Russian Space Research Institute 1965
ISRO Indian Space Research Organization 1969
NSDAJ National Space Development Agency of Japan 1969
GAC German Aerospace Center 1969
ESA European Space Agency 1975
RSC Russian Federal Space Agency 1992
CNSA China National Space Administration 1993
38. Characterization
f (x, y, z, t, D, C, S, X)
x, y = ground location
z = altitude
t = time
D = particle diameter
C = composition
S = shape
X = mixing
42. distinct terms
radiation
emission or transmission of energy
..in form of waves or particles
electromagnetic
particle (α, β, neutron)
acoustic (ultrasound,sound,seismic)
gravitational
electromagnetic radiation
radiant energy released
..by electromagnetic process
radio, infrared, visible etc.
45. How to know?
deciding criteria
𝑃
𝑅0
..three cases
< 1
P - phase function = 1
R0 - surface reflectance > 1
46. case-(i)
phase function is lesser than surface reflectance
𝑃
𝑅0
< 1
addition of aerosols
decrease
true reflection
http://earthobservatory.nasa.gov/IOTD/view.php?id=84557
47. case-(ii)
phase function is equal to surface reflectance
𝑃
𝑅0
= 1
addition of aerosols
will not change
apparent reflection
48. case-(iii)
phase function is greater than surface reflectance
𝑃
𝑅0
> 1
addition of aerosols
increase
apparent reflection
61. Challenges
clouds cover 60% of earth’s atmosphere
atmospheric temperature… aerosol phase change
sensing technologies (coverage and accuracy)
upgradation of obsolete satellites (600+ geosynchronous)
data interpretation techniques (aerosol techniques)
space infrastructure is very expensive
62. let’s summarize
remote sensing is a science, technology and art
two types of sensing: active and passive
two types of orbits: geosynchronous and polar
four characteristics: spatial, spectral, radiometric, temporal
one governing phenomenon: optical properties
challenges: surface reflectance and clouds
63. Sources
Satellite-based measurement of atmospheric aerosols
Rudolf B. Husar
Department of Energy, Environmental and Chemical Engineering,
Washington University, Missouri
Earth Observatory
National Aeronautics and Space Administration
Wikipedia
Wikimedia Foundation
and other sources as well…
64. Further Reading
Atmospheric Chemistry and Physics:
from air pollution to climate change (2006)
John H. Seinfeld - Spyros N. Pandis
Visibility: Science and Regulation (2002)
John G. Watson
Remote Sensing of Tropospheric Aerosols from Space (1999)
Michael D. King
Remote Sensing of Particulate Pollution from Space:
have we reached the promised land (2009)
Raymond M. Hoff - Sundar A. Christopher
The characterization of aerosols distributed with respect to size
and chemical composition (1970)
S.K. Friedlander
Be sure to credit the previous presenter. Bioaerosols by Mr. Ringer
Remember always, the highest energy ever produced is in sun, where fusion occurs which is nothing by a bombardment of sub-atmonic particles.
Technical fault can happen at any time, so we must be prepared.
Working knowledge of remote sensing, not a researching knowledge, but this may help you to start one.
Try to give an disclaimer at the end about the pace, technical level, acknowledgement,
Remote Sensing has many applications. Aerosol has complex behavior.
Site observation, tachymeter
Source: Earth Observatory, National Aeronautics and Space Administration
Source: Earth Observatory, National Aeronautics and Space Administration
Tacheometer or tacheymeter
A point of discussion: optical characteristics depends only on object. For changes in light, the device has to be calibrated.
Try to delete his name and put it in the end. Try to incorporate scattering and extinction in this.
Remember OZONE layer.
know
Tacheometer or tacheymeter
http://www.geo.mtu.edu/rs4hazards/ksdurst/website/lectures/RemoteSensing.pdf
ASTER Advanced Spaceborne Thermal Emission and Reflection Radiometer
Tacheometer or tacheymeter
http://www.geo.mtu.edu/rs4hazards/ksdurst/website/lectures/RemoteSensing.pdf
ASTER Advanced Spaceborne Thermal Emission and Reflection Radiometer
spatial resolution and Coverage..
spectral resolution: suppose I want a cyan. Can it separate the incident light?
sensors ability to discriminate very slight differences in (reflected or emitted) energy
Temporal resolution is the revisit period, and is the length of time for a satellite to complete one entire orbit cycle
Unit of brightness is Lumens.
Geostationary satellites have low spatial coverage than polar satellite. Why?
Human eye ability is only in visible range.
<lambda>min… <lambda>max
See.. I have details, but I don’t have sufficient space to store them. In the above example, it needs 11 bits to store the accuracy of image.
Same way as we humans cannot distinguish between different colors. We cannot differentiate between chestnut and brown.
Geostationary satellite has higher temporal resolution than polar satellite. Why?
internal mixing: physical, chemical and optical properties need to be considered jointly.
internal mixing: physical, chemical and optical properties need to be considered jointly.
Color Filter: same as you see in the mobile.
First you need to understand about optical properties of aerosol in ground. Only then you will be able to discern the pattern
What is the concentration of ozone.. change of phase or constituents..?
First you need to understand about optical properties of aerosol in ground. Only then you will be able to discern the pattern
What is the concentration of ozone.. change of phase or constituents..?
First you need to understand about optical properties of aerosol in ground. Only then you will be able to discern the pattern
What is the concentration of ozone.. change of phase or constituents..?
First you need to understand about optical properties of aerosol in ground. Only then you will be able to discern the pattern
What is the concentration of ozone.. change of phase or constituents..?