Satellite Imagery and Remote Sensing DeeDee Whitaker SW Guilford High EES & Chemistry

Outline  What 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?

 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 Reflectance

EES Sensor Ranges  Visible Spectrum- full color digital photography  Infrared- “heat” Near-Infrared- vegetation Mid-Infrared- soils  Ultraviolet- clouds and snow cover All color images require “processing”.

Differences Among Infrared Regions Near IR- ( )microns 740 K- ( K) Earth’s surface and above Mid IR 5 to (25-40) microns ( ) K to 740 K only above the atmosphere Far IR (25-40) to ( ) microns ( ) K to ( ) K only above the atmosphere Reminder : C ° = K

Visible and Near IR Comparisons AB AB

Examples of Satellite Imagery NASA 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  a.gov/Features/Landsat/  Land cover and land cover change

MODIS (Moderate Resolution Imaging Spectroradiometer)  Temporal: Daily  Spectral: 36 bands  Spatial: m   Global land cover and ocean RS  Fire monitoring

IKONOS- commercial  Temporal: On Demand  Spectral: 4 bands, panchromatic  Spatial: 1-4 m  Local land cover  ikonos.html

JASON (Active)  Temporal: 10 days  Spectral: NA (Active)  Spatial: ~ 2 km  _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   National Map-data and imagery   Imagery Sources  cmp=3913&gclid=CP20qKO6xrACFYlk7Aodw0_QoA cmp=3913&gclid=CP20qKO6xrACFYlk7Aodw0_QoA    _edit.svg _edit.svg  NASA and NOAA

Summary  Remote 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.