Remote SensingKailua Bay, Oahu, Hawaii

Pick up an Electromagnetic Spectrum

Worksheet from the front table.

You have five minutes from the time the

bell rings to complete it.

After you have completed your

Bellringer write your homework in your

Planner

Bellringer

TLW be introduced to the main concepts

of Remote Sensing

TLW be able to draw and label various

images of Oahu.

TLW be able to locate Diamond Head from

the remote sensing images of Oahu.

Ojectives

What color is the sky?

Why do you think the sky is this

color?

Is there any time when the sky is a

different color?"

Demonstration

Colors of the Sky

◦Make a prediction by describing what

you think will happen when you shine a

flashlight into the aquarium of water.

Demonstration

The shorter the wavelength of light, the more it is scattered by the atmosphere. Blue has a shorter wavelength, it is scattered ten times more than red light.

At sunset, light takes a longer path through the atmosphere. Most of the blue light has been scattered out.

Demonstration

The science of obtaining and interpreting

information from a distance, using sensors

that are not in physical contact with the

object being observed.

Remote Sensing

Hyperlink of video in picture

From atop Diamond Head. Image by H. Mamula

Haze-A visual effect when the concentration of scattering agents is high.

NIR- Near infrared Pseudoinvariant features- Manmade

materials such as asphalt and concrete, or natural materials such as deep water bodies or dry bare soil areas.

Remote Sensing Terms

Remote Sensing

What are the Three Categories of Remote Sensing Systems?

1.Reflected solar radiation sensors2.Thermal infrared sensors 3.Imaging radar sensors

Your eyes detect electromagnetic energy in the form of visible light.

Your ears detect acoustic (sound) energy Your nose contains sensitive chemical

receptors that respond to minute amounts of airborne chemicals

Examples of Remote Sensing

Eyes Ears

Nose

The science of remote sensing in its broadest sense includes:◦Aerial◦Satellite◦Spacecraft

Observations detect and measure electromagnetic energy, including visible light, that has interacted with surface materials and the atmosphere.

Remote Sensing

Remote Sensing

UNITS1 micrometer (μm) = 1 x 10-6 meters1 millimeter (mm) = 1 x 10-3 meters1 centimeter (cm) = 1 x 10-2 meters

0.4 0.5 0.6 0.7

Blue Green Red

Incoming from Sun

Emitted by Earth

INFRAREDEnergy

Wavelength

0.1 μm 1 μm 10 μm 100 μm 1 mm 1 cm 10 cm 1 m

MICROWAVE(RADAR)

ULTRAVIOLET

VISIBLE

(logarithmic scale)

Electromagnetic spectrum that is useful in remotesensing of the Earth’s surface.

Matter - EM Energy Interaction ProcessesThe horizontal line represents a boundary between two materials.

EM Energy Interaction Processes

Transmission

Emission & Absorption

EM Energy Interaction Processes

Emission

Absorption

The lower the temperature,the longer the wavelength of the emitted radiation.

Specular Reflection

EM Energy Interaction Processes

The surface is smooth

Scattering (Diffuse Reflection)

EM Energy Interaction Processes

Rougher surfaces cause scatteringin all directions.

The amount of energy absorbed varies in wavelength for each material in a characteristic way, creating a sort of spectral signature.

EM Energy Interaction Processes

Emission

EMR Source Sensor

Absorption

Absorption

Absorption

ScatteringScattering

Scattering

Scattering

EMR interactions in the atmosphere and at the Earth’s surface.

1. Reflected solar radiation sensors Detect solar radiation that has been diffusely reflected (scattered) upward from surface features.

Categories of Remote Sensing Systems

Image shows reflected red light at 650 nm in red, reflected NIR at 850 nm in green, and thermal IR at 8 - 12 um in blue as viewed from above on 26 November 2007, between 13:58 and 14:19 PST.

Image by, USDA Forest Service

Thermal infrared sensors Sensors that can detect thethermal infrared radiation emitted by surface featurescan reveal information about the thermal properties ofthese materials.

Categories of Remote Sensing Systems

Image shows reflected red light at 650 nm in red, reflected NIR at 850 nm in green, and thermal IR at 8 - 12 um in blue as viewed from above on 26 November 2007, between 13:58 and 14:19 PST.

Image by, USDA Forest Service

Thermal infrared sensors Applications of thermal infrared images are

possible, including mapping rock types, soils, and soil moisture variations, andmonitoring vegetation condition, sea ice, and ocean current patterns.

Categories of Remote Sensing Systems

Image by, USDA Forest Service

Imaging radar sensors These “active”systems “illuminate” the surface with broadcast microwave radiation, then measure the energy that is diffuselyreflected back to the sensor.

Categories of Remote Sensing Systems

Image by NASA.gov

Radar sensors can always acquire an image, independent of cloud cover or whether it is day or night, they are very useful in monitoring change over time.

Imaging radar sensors Radar images are used to map landformsand geologic structure, soil types, vegetationand crops, and ice and oil slicks onthe ocean surface.

Categories of Remote Sensing Systems

Image by NASA.gov

Hilly terrain dominates the right half andflatter surfaces the left half of this radarImage.

We can learn even more by combining image data from different sensors.

Interpretation of the merged data set can employ rigorous quantitative analysis, or more qualitative visual analysis.

Combing the 3 Categories of Image Data to Create Remote Sensing

Images of Oahu

Hyperlink hidden behind map.

Locate Diamond Head in the image Use graph paper to draw the Thematic

Mapper Simulator (TMS) image of Honolulu. The image looks quite similar to how we

would observe the city from an airplane.

Images of Oahu

Locate Diamond Head in the image Use graph paper to draw the Shuttle

Imaging Radar (SIR) image of Diamond Head.

Shows steep slopes and rough surfaces (at a wavelength of 24 cm) as very bright parts of the image, and smooth or non- reflective surfaces as dark.

Images of Oahu

In this set of three images, we inter-compare the oblique computer image with photographs taken from our aircraft flying along the coast.

Images of Oahu

Use the set of three images from the previous page & the map of Oahu to locate the following locations:

1. Pearl Harbor2. Waikiki Beach3. Queen Emma’s Summer Palace4. Punch Bowl National Cemetery

Images of Oahu

What are the Three Categories of Remote Sensing Systems?

Conclusion

What are the Three Categories of Remote Sensing Systems?

1. Reflected solar radiation sensors

Conclusion

What are the Three Categories of Remote Sensing Systems?

1. Reflected solar radiation sensors2. Thermal infrared sensors

Conclusion

What are the Three Categories of Remote Sensing Systems?

1. Reflected solar radiation sensors2. Thermal infrared sensors 3. Imaging radar sensors

Conclusion

1. NASA.gov. Retrieved on February 17, 2010. http://southport.jpl.nasa.gov/cdrom/sirced03/cdrom/DOCUMENT/HTML/TEACHERS/MODULE02/MOD2SECB.HTM

2. Oahu Map. Retrieved on February 18, 2010. http://www.alohaupdate.com/Oahu/Images/oahu.jpg

3. Smith, R. Ph.D., 23 August 2006. Introduction to Remote Sensing Environment (RSE). MicroImages, Inc., 2001–2006 Microimages.com. Retrieved on February 17, 2010. http://www.microimages.com/getstart/pdf/introrse.pdf

Resources

5. USDA Forest Service. Retrieved on February 17, 2010. www.fireimaging.com/.../330/locmap%20copy.gif

6. Virtually Introduction to Remote Sensing Environment. Retrieved on February 17, 2010. http://satftp.soest.hawaii.edu/space/hawaii/vfts/oahu/rem_sens_ex/rsex.spectral.4.html

7. Wittlin, M. 8 October 2006. Beauty is in the Processing-Time of the Beholder. Brain & Behavior. Retrieved on February 17, 2010. http://seedmagazine.com/.../attractive_article.jpg

Resources