What is the evidence that Venus once possessed more water than it does today? How did it lose its water, and how did its atmosphere evolve afterward?
What will be an ideal response?
Venus is thought to have lost its water through H escape through the top of the atmosphere, caused by a wet stratosphere that allowed photolysis of water molecules and the creation of H radicals. The evidence for this is the high deuterium/hydrogen ratio in Venus's atmosphere, which indicates that hydrogen was preferentially removed from the system, as would be expected for H escape.
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People in urban areas tend to have better access to medical services, family planning and recycling facilities than people in rural areas.
Answer the following statement true (T) or false (F)
Why is land use planning typically more effective than artificial control of natural hazards?
A) Land use planning often reduces the probability that a hazardous event will occur. B) Most hazardous natural processes are not amenable to artificial control. C) Artificial controls usually increase the probability that a hazardous event will occur. D) Land use planning is an accepted societal tool for hazards, while artificial control is not.
For observers in the Norther Hemisphere, which of the following is true?
A) Day length is longest on the summer solstice and is shortest on the winter solstice. B) Day length decreases from the winter solstice until the vernal equinox, then it begins to increase. C) Day length is most pronounced on the equinoxes and least variable on the solstices. D) Day length becomes increasingly longer during the period from the summer solstice until the winter solstice. E) Day length variations are negligible for all locations throughout the year except north the Arctic Circle.
The seasonality of precipitation for the Humid Continental climate in North America can best be explained by
A. westerly migration of mid-latitude cyclones. B. monsoonal precipitation. C. the moist western side of the subtropical high. D. the moist eastern side of the subtropical high.