Lab 2 Weather & Climate PDF

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second lab...

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Q1: What layer of the atmosphere is below the stratosphere? Troposphere Q2: What gas has a higher concentration in the stratosphere than in the troposphere? High concentrations of ozone gas, low concentrations of water vapor Q3: What does the atmosphere do to most of the UV radiation from the Sun? When the ozone layer is in tact, it absorbs 50% of the UV-A radiation, 90% of the UV-B radiation, and all of the UV-C radiation coming from the sun.! Q4: What three conditions are needed for CFCs to cause a “hole” in the ozone layer over Antarctica? There are three conditions that are needed for CFCs to be able to efficiently destroy ozone molecules and cause major decreases in ozone concentrations in the stratosphere: (1) solar radiation,!(2) low temperatures, and!(3) a surface on which the ozone-destruction process can occur. Q5: Why was the Montreal Protocol enacted and when was it signed? September 1987 to phase out the production and use of CFCs

Q6: What is the range in concentrations of stratospheric ozone during the course of the year over Atlanta? What does this indicate about the amount of change of ozone over the course of the year? During the beginning of the year, the ozone concentration levels are in the high 200’s to the low 300’s, and while the seasons change in May and June, the levels raise slightly to the mid to high 300’s. As we approach December of 1997, the levels lower to the low 200’s. Q7: What is the range in concentrations of stratospheric ozone during the course of the year over the Arctic Circle? What does this indicate about the amount of change of ozone over the course of the year? During the beginning of the year, the ozone level in the Arctic circle is not measured, and as the year goes on, the levels begin to rise, however in September until the end of the year, the levels are not measured Q8: What is the range in concentrations of stratospheric ozone during the course of the year over Antarctica? What does this indicate about the amount of change of ozone over the course of the year? Over Antarctica, at the beginning of the year, the levels are around 200, and are not measured between May and August. In August, levels are below 200, however begin to rise again and by November are around 250, and continue to rise into the 300’s by December. Q9: What value for the Dobson Units would constitute a true hole in the ozone layer? Based on this answer, did the data from 1997 show a true hole in the ozone layer over any place on Earth?

In October, the levels are drastically below 220 Dobson Units and this would constitute a hole in the ozone layer in Antarctica.

SQ10: During what months of the year do the lowest ozone concentrations tend to occur? What season is this for Antarctica?!Keep in mind that Antarctica is in the Southern Hemisphere. During the fall, the levels in Antarctica are the lowest, in Atlanta it is during the winter, and in the Arctic Circle it is hard to determine as the levels are only measured during the spring and summer, with the lowest point being during August. SQ11:!Based on the three factors that you identified in Q4, Why do you think those months had the lowest ozone concentrations? I believe they are lowest during these months due to the low temperature because of the changing seasons. Q12: Based on what you observed in the animation, on what day(s) did the severe destruction zone migrate over Tierra del Fuego? Around October 12th SQ13: How did the change in ozone concentrations affect the amount of UV radiation reaching the Earth’s surface? As the ozone concentration lowers, more UV radiation has the ability to enter the earth SQ14: What affect did the change in UV radiation have on the vegetation?

On October 14th, when more UV radiation was let in to the atmosphere on top of Tierra Del Fuego, the DNA damage was higher by one unit than it was on October 17th. However both these days still brought in DNA damage to the vegetation. SQ15: Based on your answers to Q13 – Q14 and the data you examined, explain whether it would be reasonable for a scientist to state that, “Significant decreases in ozone concentration over a part of the Earth can!cause!serious damage to plant and animal DNA.” This would be a valid hypothesis to state, based on the evidence of the DNA damage that was incurred of the vegetation found in Tierra Del Fuego. Q16: How would you describe the trends in the data over time for the spring ozone concentration over Antarctica from 1979 to 1989? i.e. What do you see happening to the ozone concentration over Antarctica in the time since!the Montreal Protocol went into force? The levels of ozone concentration between those years starts high are around 225 DUI and drops below 150 in 1987 before jumping back to 175 in 1989. Q17:!How would you describe the trends in the data over time for the Hole Area over Antarctica from 1979 to 1989? i.e. What do you see happening to the!Hole Area!over Antarctica in the time since!the Montreal Protocol went into force? By 1989 the hole size drastically from where it was in 1987, dropping below 10 million km2; roughly half of its size in 1986-87. In 1979 it was at roughly at 0.1 million km2.

SQ18:!Based on your answers to Q16 and Q17, what is the relationship between ozone concentration and Hole Area? As ozone concentration goes up, hole area shrinks, as we can see in the data in 1987 SQ19: You should notice in the graph that between 1987 and 1988 and then again between 2001 and 2002, there were very dramatic decreases in the Hole Area (or severe destruction zone). If the amount of UV radiation and the amount of ozone–destroying chemicals did not change significantly over those two periods,!why did the Hole Area change so dramatically? I believe the hole are changed drastically due to the higher solar radiation and lower temperatures during those years. SQ20: Based on your analysis of the graph, what effect has the Montreal Protocol had on the stratospheric ozone layer? The Montreal Protocol has had a positive effort on reducing the ozone depleting substances and we can see this in the graph as the levels of ozone concentration shift. SQ21: You should have noticed that the Hole Area leveled off but did not decrease significantly since the Montreal Protocol was put in place; why has it not decreased significantly yet? The Montreal Protocol has greatly decreased since it was put in place however the Ozone layer is not expected to reach pre 1979 levels until roughly 2050-2070

SQ22: For the entire visible area of the animation, why do the two scenarios have similar results in the 1970s and 1980s? HQ23: What effect should the Montreal Protocol have on the stratospheric ozone layer in future decades? As more ozone depleting substances become banned and phased out, the ozone layer will have the opportunity to heal and eventually reach pre 1979 levels.

HQ24: If the phasing out and elimination of ozone-destroying chemicals had not occurred, then what do you expect would happen to the rate of UV-caused health problems among people between now and 2060? The rate of skin cancer, lung disease and other lung problems would have increased significantly....