第二章：遥感物理基础

Application and Theory of Remote Sensing Chp2:Physical Basis of RS遥感的物理基础大气对辐射的影响（了解）大气窗口（理解并掌握）太阳及地球的辐射特性（了解）地物波谱曲线及典型地物波谱曲线特征（理解并掌握）本章讲授内容及要求电磁波及电磁波谱的概念（掌握遥感所用的谱段）Application and Theory of Remote Sensing Chp2:Physical Basis of RS2.1 电磁波谱与电磁辐射Application and Theory of Remote Sensing Chp2:Physical Basis of RS2.1.1、电磁波谱AM:调幅 (Amplitude Modulation)Application and Theory of Remote Sensing Chp2:Physical Basis of RSApplication and Theory of Remote Sensing Chp2:Physical Basis of RSBand Wavelength Rays 0.7 m). Eyes are only sensitive to light from the 0.4 to 0.7 m. Remote sensor detectors can be made sensitive to energy in the non-visible regions of the spectrum. The Sun produces a continuous spectrum of energy from gamma rays to radio waves.Application and Theory of Remote Sensing Chp2:Physical Basis of RSApplication and Theory of Remote Sensing Chp2:Physical Basis of RSApplication and Theory of Remote Sensing Chp2:Physical Basis of RS2.2.2 大气吸收 1.大气层次与成分分子 ( molecules ) 99% N2 ; O21% O3 ;CO2 ;H2O微粒 ( particles ) 烟尘、小水滴、固体悬浮物、气溶胶（固、液悬浮物）Application and Theory of Remote Sensing Chp2:Physical Basis of RS2.大气对辐射的吸收 ( Absorption )作用 特定的气体吸收特定的波长，如 Ozone 吸收紫外线， carbon dioxide ： 吸收远红外线，可产生热量（ greenhouse ) 大气分子对电磁波的某些波段有吸收作用，从而引起这些波段太阳辐射强度的衰减，甚至某些波段的电磁波完全不能通过大气。Application and Theory of Remote Sensing Chp2:Physical Basis of RSSuns Absorption SpectrumH2O 0.94; 1.13; 1.38; 1.86; 2.53.0; 3.24; 57;CO2 2.8; 4.3O3 0.20.32O2 0.2; 0.6; 0.76Application and Theory of Remote Sensing Chp2:Physical Basis of RS2.2.3大气散射 ( scattering )电磁辐射在传播过程中遇到小的微粒而使传播方向改变，并向各个方向散开， 称散射。 散射使原传播方向的辐射强度减弱，而增加向其它方向的辐射。尽管散射的强度不大，但从遥感数据角度分析，太阳辐射在照射到地面后又反射到传感器的过程中， 二次通过大气， 在照射地面时，由于散射增加了漫入射