Archiv: Carl Sagan


21.02.2021 - 14:10 [ Carl Sagan, George Mullen / University of Texas at Austin ]

Earth and Mars: Evolution of Atmospheres and Surface Temperatures

(7. Juli 1972)

Indeed, detailed global climatic models (17) suggest that a relative increase in A of only 2 percent is enough to induce extensive glaciation on Earth, which implies that the present climate is extremely sensitive to albedo. This leaves changes in atmospheric composition as a possible explanation. Major variations in the CO2 abundance will have only minor greenhouse effects because the strongest bands are nearly saturated. A change in the present CO2 abundance by a factor of 2 will produce directly a 2° variation in surface temperature (18). The CO2 abundance is highly controlled by silicate-carbonate equilibria; by buffering with seawater, which contains almost 100 times the atmospheric CO2; and by the respiration and photosynthesis feedback loop (19).

20.02.2021 - 12:27 [ Erik Wernquist / Vimeo ]

Wanderers

With kind permission from Ann Druyan, the narration by Carl Sagan is now back in the film.
Also, the film is now available for DOWNLOAD for your private full quality viewing pleasure.