Difficulty: Easy
Correct Answer: All of these
Explanation:
Introduction / Context:
Remote sensing signals arise from how materials interact with incident radiation. The balance among reflection, absorption, emission, and transmission determines the signatures detected by optical, thermal, and microwave sensors.
Given Data / Assumptions:
Concept / Approach:
For any wavelength λ, the interaction can be summarized: R(λ) + A(λ) + T(λ) = 1 (fractions). Absorbed energy increases internal energy and later appears as emission according to temperature and emissivity. Reflectance, transmittance, and emittance vary with material composition, moisture, surface roughness, and structure, creating diagnostic spectral features.
Step-by-Step Solution:
Identify reflection as the component sensed by passive optical instruments.Recognize absorption features (e.g., pigment, water) that reduce reflectance at specific bands.Account for re-radiation: absorbed energy is emitted at thermal wavelengths proportional to temperature.Include transmission relevant to semi-transparent media (water, leaves, thin films).Therefore all listed interactions are possible; select the combined option.
Verification / Alternative check:
Spectral libraries show characteristic reflectance dips (absorption bands) and thermal emissivity peaks, confirming the energy partition concept across wavelengths.
Why Other Options Are Wrong:
Single-process options ignore the full energy balance; real targets exhibit multiple simultaneous pathways.
Common Pitfalls:
Assuming reflectance alone explains sensor readings; neglecting transmission in vegetation canopies or emission in thermal infrared.
Final Answer:
All of these.
Discussion & Comments