Spectral Exitance (Temp. &  )  = 1.0

Earth’s reflective (sun) & emissive (reradiation) regions

Inverse distance & intensity 5880 K: 6.8 x10 7 W/m W/m W/m W/m 2 C->P: 7x10 8 m C->V: 1.0x10 11 m C->E: 1.5x10 11 m C->M: 2.3x10 11 Total: 4.1x10 26 W

Inverse distance & intensity

Visible-thermal-microwave

Spectral Reflectance Asphalt & Concrete R =1-A Spectral Reflectance Asphalt & Concrete R =1-A

Green Veg & Astroturf R =1-A Green Veg & Astroturf R =1-A

In situ Spectra of Fall Leaves Wavelength (µm) Reflectance (%) Fall Leaves

Green leaves from a broadleaf tree beginning to change color as nutrients withdraw into the tree core Deciduous broadleaf tree with its colors changed and some leaves fallen on the ground Broadleaf Trees Changing Color

R =1-A Green Veg & Fall Colors R =1-A

Plant Pigments So, what absorbs in functioning leaves? (Reflectance = Absorption 

Snow, Clouds, Water, Soil, & Green Veg R =1-A R =1-A

Snow, Clouds, Water, Soil, & Green Veg R =1-A Snow, Clouds, Water, Soil, & Green Veg R =1-A

Basic Interactions between Electromagnetic Energy and the Earth’s Surface R =1-A R =1-A

Specular versus Diffuse Reflectance R =1-A R =1-A

Bidirectional Reflectance of Black Spruce & Jack Pine in shadow no shadows R =1-A R =1-A

Bidirectional Reflectance of Black Spruce & Jack Pine in shadow no shadows R =1-A R =1-A

Bidirectional Reflectance of Black Spruce & Jack Pine in shadow no shadows R =1-A R =1-A

~1370 watts/m 2 M =  T 4  Total Energy Flux: M =  T 4 (w/m 2   = 5.67x10 -8 w/m 2 *K 4

92%

Incoming/Outgoing max = 2898/5880 = 0.49  m max = 9.7  m

Solar Irradiance at Earth’s Surface Exoatmospheric Solar Irradiance atmospheric limb

Stefan-Boltzman constant Radiation Speed of light = * frequency

Total Energy Flux: M =  T 4   = 5.67x10 -8 w/m 2 *K 4 Wavenumber = 1/ (#  per unit distance) Energy per photon: E p = h * frequency E p = h*c/  E p  *   J sec *3*10 8 m sec -1 Ergo: X-rays and  -rays are energetic!

Rayleigh Scattering: why the sky is blue 1  

Kirchoff’s Radiation Law For any object that intercepts EM radiant energy r +  +  = 1 at thermal IR wavelengths,  = 0 and  =  Therefore 1 = r + 

Apparent Radiant Temperature - T rad  - radiant flux – the amount of radiant energy per unit time pass through or from an object T rad is simply the radiant flux being emitted by an object because of its temperature, the radiant temperature

Kinetic vs. radiant temperature  T rad 4 =  T kin 4 ; T rad =  1/4 T kin

FLIR Images

Thermal history of helicopters