GEO 420 Dr. Garver. What is remote sensing What is it used for History

GEO 420Dr. Garver

What is remote sensing

What is it used for

History

remote sensing (v) the science of deriving information about the earth's land, atmosphere and water areas from images acquired at a distance.

Relies on measurement of electromagnetic energy reflected or emitted from the features of interest.

1950s - term coined by Evelyn Pruitt

Geographer/oceanographer with U.S. Office of Naval

Research (ONR).

Term was devised to take into account the new views

from space obtained by the early meteorological

satellites which were more "remote" from their targets

than the airplanes that up until then provided aerial

photos as the medium for recording images of the

Earth's surface.

Main Entry: syn·op·tic

Function: adjective

Etymology: Greek synoptikos, from

synopsesthai

1 : affording a general view of a whole

2 : manifesting or characterized by

comprehensiveness or breadth of view

3 : relating to or displaying conditions (as of

the atmosphere or weather) as they exist

simultaneously over a broad area

Tornadoes - F-5 - largest and most powerful classification - winds 300 m/h.TGOES-East weather satellite produces images of most of U. S. every 30 min. in vis and IR wavelengths.

Pronunciation: "re-z&-'lü-sh&n”

Function: noun

the process or capability of making

distinguishable the individual parts of

an object, closely adjacent optical

images, or sources of light.

the point in a literary work at which the chief

dramatic complication is worked out.

Unique view of our planet.

Remote sensing allows us to examine, in

unprecedented detail, characteristics of

our atmosphere, oceans, and land areas.

Use sensors to view the spectral and

spatial relations of objects at a distance.

CZCS

The term "photography" is derived from

two Greek words meaning "light" (phos)

and "writing" (graphien).

No one knows when humans first

constructed a device that would record

images by means of light

The First PhotographThe First Photograph

first photograph obtained by Joseph Nicephore Niepce of his French estate courtyard in 1827. Exposure lasted 8 hours.

first photograph obtained by Joseph Nicephore Niepce of his French estate courtyard in 1827. Exposure lasted 8 hours.

Put sheets of silver salts at back of camera obscura, known to blacken with daylight. Called these images “retinas“ .

First known aerial photograph was obtained by Gaspard Felix Tournachon (Nadar) from a tethered balloon 1,700-ft. above Paris, France in 1858.

Took first photographs in 1853 and in 1858 became the first person to take aerial photographs

First known aerial photograph was obtained by Gaspard Felix Tournachon (Nadar) from a tethered balloon 1,700-ft. above Paris, France in 1858.

Took first photographs in 1853 and in 1858 became the first person to take aerial photographs

1850s- balloonists took pictures of ground using newly invented photo-camera.

Oblique photograph obtained from the Hippodrome Balloon using a multiband camera.

Also pioneered the use of artificial lighting in photography, working in the catacombs of Paris.

Oblique photograph obtained from the Hippodrome Balloon using a multiband camera.

Also pioneered the use of artificial lighting in photography, working in the catacombs of Paris.

Served as a prime remote sensor for more than 150

years.

Captures image of targets exterior to it by

concentrating electromagnetic (EM) radiation

(visible light) through a lens onto a recording

medium.

Key advance occurred in 1871 - development of

photographic negative.

Silver halide film remains the prime recording

medium today.

Film displays objects by variations in brightness of

gray levels (black and white) or color tones.

Late 1800s – Early 1900s Pigeon fleet used to carry cameras

Photograph of a castle taken automatically by a camera strapped on a pigeon in flight

Aerial photography - reconnaissance tool in WW I and II

1946 - Remote sensors in space began with photo-camera systems on captured German rockets.

Power and capability of launch vehicles big factor in determining what remote sensors could be placed as part of the payload.

Dawn of the Space Age – R. S. above the atmosphere (both Russian and American).

• 1957 - Soviet Union launched Sputnik I • World's first artificial satellite• Size of a basketball, 183 pounds• Ushered in new political, military, technological, and scientific developments. • Start of the space age and U.S.-U.S.S.R space race.

First ever U.S. satellite in Earth orbit designedto image and monitor weather. TIROS-1, launched April, 1960 soon after NASA came into existence.

Image is considered the official start of remote sensing from satellites.

First cosmonauts/astronauts used

hand-held cameras.

1960’s - Black and white TV-like

images of Earth from

meteorological satellites.

First non-photo sensors were television cameras mounted on unmanned spacecraft to look at

clouds.

TIROS-1

Superimposed on

cloud patterns is a

generalized weather

map; this kind of

data display soon

started to appear in

television news

broadcasts.

1961 - First American in Space?

1970's – matured - repetitive

schedule instruments on

Skylab ( then Space Shuttle)

Landsat - first satellite dedicated to

mapping natural and cultural

resources on land and ocean surfaces.

Set stage for other satellite systems

Demonstrated power & versatility of

multispectral imagery* for observing Earth

Monitors natural & human made features over

time.

Since 1972, six Landsats have been orbited

successfully.

*multispectral scanner-Scanner system that simultaneously acquires

images of the same scene at different wavelengths.

Early Landsat image (Utah 1972)

1978 - radar imaging system main sensor on Seasat.

First satellite designed for remotesensing of oceans with SAR.

Mission - demonstrate feasibility of global satellite monitoring of oceans.

Collect data on sea-surface, winds, SST, wave heights.

1980 - specialized sensors

Coastal Zone Color Scanner (CZCS)

Ocean color = biology

Advanced Very High Resolution

Radiometer (AVHRR)

Vegetation cover, SST

Space shuttle (1982) - JPL's Shuttle

Imaging Radar (SIR-A).

Sea Surface Height

Main Entry: ra·di·om·e·ter

Pronunciation: "rA-dE-'ä-m&-t&r

Function: noun

: an instrument for detecting and

measuring the intensity of radiant

energy;

- ra·di·om·e·try /-m&-trE/ noun

CZCS image of Gulf Stream - April 1982 - warm-core ring.

AVHRR - SST

1980s - Landsat privatized,

widespread commercial use of

remote sensing.

Improved sensor - Landsat-5

Thematic Mapper (TM; 30m

resolution).

Improvement in detail of later Landsats owing to new sensor.

Mosaics - images of entire Earth or continents.

Color view of continental U.S from summer

AVHRR.

Notice regionally variable distribution of

vegetative cover (green).

Variety of sensors on land and sea

satellites

Launched by U.S. govt., private U.S.

industry and other countries.

Most observe in;

Visible

Near IR

Thermal infrared

Some radar

Land observers ‘72 – ‘96

Remote sensing has become major

tool for monitoring

earth/atmosphere system.

BIG BUCKS SPENT on applications

for environmental and natural

resource management.

Huge improvements in;

Computer-based image processing

PC’s can handle large amounts of

data

Makes data accessible to

universities, govt. agencies,

environmental companies, and

individuals.

Satellites ‘95 – ‘05Note # of commercialsatellites.

Spain and NW Africa – Feb. 13, 2001. Dust blowing off Sahara forms question mark over Atlantic Ocean west of Spain.

Commercial Data- OrbimageSeaWiFS sceneNear true color

1999 - reliable stream of image data that has become the standard for commercial high-resolution satellite data products.

IKONOS produces 1-meter black-and-white (panchromatic) and 4-meter multispectral (red, blue, green, near infrared) imagery.

Wide range of high-resolution imagery applications.

Before Sept. 11

IKONOS

After Sept. 11

IKONOS

1m res satellite image of Manhattan on Sept. 12, 2001 by Space Imaging's IKONOS satellite.

Shows an area of white and gray-colored dust and smoke at the location where the 1,350-foot towers of the WTC once stood.

IKONOS

IKONOS

Commercialization of space imagery is

currently a huge deal in the remote sensing

field.

Emergence in 21st Century of private,

commercial satellite operations

Rather than continued dependence on

NASA/NOAA, space agencies in other

countries, and the military to provide useful

imagery.

But remote sensing operations are still in

large part government-driven (U.S. and Intl).

Huge need to monitoring terrestrial

systems.

observe, quantify, map changing land use,

protect natural resources,

track interactions within the biosphere,

atmosphere, hydrosphere, and geosphere