Satellite Imagery and Remote Sensing

DeeDee WhitakerSW Guilford HighEES & Chemistrywhitakd@gcsnc.com

OutlineWhat is remote sensing?How does remote sensing work?

What role does the electromagnetic spectrum play in satellite imagery?

How can satellite imagery be applied in science classrooms?

Common Vocabulary Remote sensing- gathering data without direct

contact. Satellite- in this case, a man-made machine

orbiting the Earth that collects reflected radiation from the Earth’s surface.

Pixel-picture element or the size of the digital block of information

Resolution- the “clarity” or amount of data stored in a pixel. Resolution relates to pixel size. The smaller the pixel the greater the resolution.

Identifying, observing, and measuring an object without coming into direct contact with it (NASA)

What is remote sensing?

So many satellites and sensors

According to NASA-there were about 3000 satellites operating in Earth orbit in 2012.

US Satellite Orbits

Constellation

Satellite imagery is a special case of digital photography.

Radiation bands in the electromagnetic spectrum that are reflected from the Earth’s surface back into space can be collected by satellite sensors and stored digitally as pixels.

The most common electromagnetic bands for satellite imagery are visible light, near infrared radiation (NIR), and infrared radiation (IR).

How does Remote Sensing work?

http://marine.rutgers.edu/mrs/education/class/yuri/erb.html

Some satellites collect only the radiation that that is reflected from the surface of the earth. (Passive)

Other satellites like JASON, emit radiation at 13.6 GHz and 5.3GHz and measure the time it takes for the “round trip”. (Active)

Active satellites measure elevation and are used to generate topography.

What role does the Electromagnetic Spectrum play in RS?

Reflectance

http://accessscience.com/search.aspx?rootID=796762

EES Sensor RangesVisible Spectrum- full color digital photographyInfrared- “heat”

Near-Infrared- vegetationMid-Infrared- soils

Ultraviolet- clouds and snow cover

All color images require “processing”.

Differences Among Infrared RegionsNear IR- (0.7 - 1)microns

740 K- (3000-5200 K) Earth’s surface and above

Mid IR 5 to (25-40) microns (92.5-140) K to 740 K only above the atmosphere

Far IR (25-40) to (200-350) microns (10.6-18.5) K to (92.5-140) K only above the atmosphere

Reminder : C° + 273 = K

Visible and Near IR ComparisonsA B

A B

Examples of Satellite ImageryNASA and Google Earth

How can scientists use IR data to study the earth’s surface?

Kohrs, Infrared Image

Landsat Program

Temporal: 16 days

Spectral: 4-8 bands

Spatial resolution: 30 m

http://earthobservatory.nasa.gov/Features/Landsat/

Land cover and land cover change

MODIS (Moderate Resolution Imaging Spectroradiometer)

Temporal: DailySpectral: 36 bandsSpatial: 250-1000 m http://modis.gsfc.nasa.gov/about

Global land cover and ocean RS

Fire monitoring

IKONOS- commercial

Temporal: On DemandSpectral: 4 bands, panchromaticSpatial: 1-4 mLocal land cover http://www.satimagingcorp.com/

gallery-ikonos.html

JASON (Active)Temporal: 10 daysSpectral: NA (Active)Spatial: ~ 2 km http://ilrs.gsfc.nasa.gov/satellite_missions/

list_of_satellites/jas2_general.html

Sea level

How can satellite imagery be applied to

EES classrooms? Weather forecasting

Storm tracking Ocean temperature monitoring Sea level changes Large scale land

mass & land use changes

Resources NC OneMap-data and imagery

http://www.nconemap.com/

National Map-data and imagery http://nationalmap.gov/viewer.html

Imagery Sources http://www.info.com/nasa%20satellite%20imagery?cb

=27&cmp=3913&gclid=CP20qKO6xrACFYlk7Aodw0_QoA

http://weather.msfc.nasa.gov/GOES/ http://www.goes.noaa.gov/ http://

en.wikipedia.org/wiki/File:EM_Spectrum_Properties_edit.svg

NASA and NOAA http://eospso.gsfc.nasa.gov/

SummaryRemote sensing allows us to

observe and monitor the earth surface.

Features on the Earth’s surface can be interpreted using spectral/electromagnetic information.

Satellites have a wide range of purposes.