GEOG309 Lecture Notes - Lecture 4: Black Body, Emissivity, Shortwave Radio

• School: University of Waterloo
• Department: Geography and Environmental Management
• Course: GEOG309
• Professor: Yuri Leonenko

Document Summary

There is almost no absorption of solar radiation by our atmosphere, but almost all of. Initial thought: you can almost consider atmosphere as a black. Body (for earth"s radiation: in reality, greenhouse effect is not that strong b/c atmo is not completely black body, model provides nature of the greenhouse effect: atmospheric absorption & additional flux of energy. Absorption is different @ different layers of atmo: also, atmo has 2 surfaces. Upper surface facing sun and lower surface facing. Earth"s emission temperature is still always 254 k, but it"s controlled by the atmosphere, not by surface. Atmo acts like a black body (emitting radiation) Atmo is nearly transparent to solar radiation (clear. More accurate: not all of earth"s radiation is absorbed by atmo, < 1: Longwave emission (upward: greenhouse effect is more moderate compared to previous assumption (of bb atmosphere, explains. Longwave emission (downward) conditions for global warming increasing. Visible spectrum still passes through atmo with no absorption.