David was visiting the natural history museum. He noticed two charts that showed the climatic conditions of the earth in two time periods, time A and time B. Time A showed earth's overall climate in the sixteenth century when there were less greenhouse gases in the atmosphere. And time B showed earth's overall climate in the present century with more greenhouse gases in the atmosphere. David found some interesting differences between these two charts. Would time B see less or more trapped terrestrial radiation than time A? Hint: Greenhouse Effect: The solar energy reaching the surface of the Earth is concentrated in short wavelengths, which can easily penetrate the greenhouse gases, such as carbon dioxide and methane. The Earth, however, is cooler than the sun and it radiates its heat in the form of energy in the far infrared range. These longer wavelengths are partially absorbed by the greenhouse gases and some of the solar heat is returned to Earth. At a certain temperature these processes are in equilibrium and the surface temperature of the Earth is stable. However, if more greenhouse gases are put in the atmosphere the amount of trapped terrestrial radiation increases, leading to an increase in global temperature.
Ans: more

Two scientists went to Antarctica for research. Tim was assigned to East Antarctica, while John was assigned to West Antarctica. They spent 6 months there. Which scientist experienced less precipitation? Hint: East Antarctica is colder than its western counterpart because of its higher elevation. Weather fronts rarely penetrate far into the continent, leaving the centre cold and dry. Despite the lack of precipitation over the central portion of the continent, ice there lasts for extended periods. Heavy snowfalls are common on the coastal portion of the continent, where snowfalls of up to 1.22 metres (48 in) in 48 hours have been recorded.
Ans: John

Gary and Joe are two farmers. Joe's farm has a depleted soil, while Gary started agroforestry a few years back, and grows cover crops. Which farmer didn't increase infiltration to prevent erosion? Hint: Depleted soils can be protected from soil erosion by groundcover plants such as naturally growing grasses in agroforestry systems. These help to stabilise the soil as they increase cover compared to short-cycle cropping systems. Soil cover is a crucial factor in preventing erosion. Cleaner water through reduced nutrient and soil surface runoff can be a further advantage of agroforestry. The runoff can be reduced by decreasing its velocity and increasing infiltration into the soil. Compared to row-cropped fields nutrient uptake can be higher and reduce nutrient loss into streams.Further advantages concerning plant growth:
Ans: Joe

John was reading about a fascinating story of a scientist in a science fiction book. In that novel the scientist met with a mysterious wormhole while visiting Antarctica. First, the wormhole started the time travel in present day, which was designated as point A. Then it sent the scientist to 170 million years in the past, which was designated as point B. The scientist had the rare experience of visiting Antarctica in two different time periods, 170 million years apart. Would there be less or more life forms in point B than in point A? Hint: More than 170 million years ago, Antarctica was part of the supercontinent Gondwana. Over time, Gondwana gradually broke apart, and Antarctica as we know it today was formed around 25 million years ago. Antarctica was not always cold, dry, and covered in ice sheets. At a number of points in its long history, it was farther north, experienced a tropical or temperate climate, was covered in forests, and inhabited by various ancient life forms.
Ans: more