Science Short Answers on Exam Questions Sample
Question 1: What is the evidence that fluctuations in green house gasses (CO2) are related to global temperature change?
The greenhouse effect makes the earth warmer than it ought to. The temperatures of the earth come to their highest when the concentration of the carbon dioxide is at its highest. The warmth of the land is thus directly proportional to the concentration of the carbon dioxide gas. As the temperatures decrease, the level of concentration of carbon dioxide in the atmosphere drops. The decline in temperatures enables more carbon dioxide gas to dissolve in the cold oceans. The atmosphere regularly exchanges the CO2 with the oceans. The cooling of the climate results in the drop of the CO2 concentration. As the climate warms, the atmosphere receives more CO2 resulting in an increase in the global temperature.
Question 2: Name at least four natural systems exchangee and regulate CO2 to atmosphere.
The four natural systems that are responsible for the exchange and regulation of CO2 to the atmosphere include
- It extracts carbon dioxide from the air.
- The process adds the amount of carbon dioxide in the atmosphere.
- The ocean. The ocean exchanges Carbon dioxide with the atmosphere by the process diffusion.
- Biological pump. The organism extracts carbon dioxide from the atmosphere.
Question 3: What is the evidence human activities are adding CO2 to atmosphere and thus increasing earth’s temperature? Why can’t this increase be attributed to natural causes?
The man-made level of CO2 amounts to 77%. This amount cannot be attributed to the natural causes because people emit more CO2 than what flora can absorb. The consuming of electricity emits more than 41% of CO2. The locomotives for transport are the second largest emitter of CO2. Industrial manufacturing emits more than 2% of CO2. Deforestation means that plants cannot absorb CO2, thus increasing its concentration. The higher the CO2 level translates to increase in the global temperature.
Question 4: List and briefly describe at least five undesirable effects of human induced climate change?
The Five undesirable effects of human-induced climate change include:
- Greenhouse effect. This has increased global warming by more than 0.8°C.
- This has reduced CO2 absorption.
- Air pollution has increased acidity in the atmosphere.
- Climate difference. Human activities have changed the climate patterns of different regions.
- Biodiversity loss. Precipitation, increased extremes of heat and acidification of oceans result from high level of CO2.
Question 5: What is “ feedback”? How do feedback mechanisms come into the discussion of climate change? Give one example of negative and positive feedback.
A feedback is the process of changing one quantity as a result of change in the second quantity, and vice versa. Feedback mechanisms. The feedback mechanisms are responsible for forcing the climate system to change i.e. radiative forcing. A greenhouse is an example of a positive feedback whereas; a negative feedback consists of the rate of warming decrease.
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Question 1: Why may a potential asteroid or comet impact be the ultimate catastrophe?
A potential asteroid or comet impact would be the ultimate catastrophe because, they ejects the dust into the atmosphere. They also emit smoke from the global fire. These effects can result in a very significant climate that will affect the global agriculture thus threatening starvation. Globally, one-quarter or more of the world population would most likely perish.
Question 2: Describe the Tunguska (siberia) event. How much energy was involved? What was the impact considered “lucky” ? What is a “comet” or a “meteor”?
An asteroid hit Tunguska in Siberia on 30th June, 1908. The object was too small, of between 30 and 60 meters across. Due to the small size, the asteroid could not be spotted easily. The cause of the event was a big volatile-rich asteroid that exploded as a result of re-entry heating. It exploded before reaching the surface, about 15,000 feet. It released energy of between 10 to 15 megatons of TNT, 1000 times greater than a nuclear bomb. The effect of the asteroid was considered fortunate because it burst in the air before it could hit the surface of the ground. It did not therefore, destroy the surface of the earth at all.
A comet is a very minute body belonging to the solar system which revolves around the sun. They display a coma that is visible when near the sun, and they sometimes show a tail. A meteor meteoroid that burns up when it passes through the atmosphere of the earth. It is sometimes called a shooting star, which is observed as a streak of light.
Question 3: Discuss the probability we will be wiped out by an impact event. Is it crazy to think so?
The impacts of big asteroids are very tiny, but the risks of people dying in the event are very high. The number of persons killed by the impact can be very significant too. To lead to a worldwide catastrophe, the impact event needs to be so big that it emits a large amount of dust in the earth’s atmosphere. The dust will cause an abrupt change in the climate that will destroy and wipe out the people. The idea is crazy though because the space guard survey consistently attempts to locate the track the near the earth objects (NEOs). They reduce the impacts of the NEOs thus reducing the chances of wiping people out of the land in case of such an event.
Question 4: Discuss the K-T boundary event. What is the evidence hat occurred? That it caused the mass extinction of life?
The event took place more than 66 million years ago. It killed the dinosaurs and animals, which happened at the end of the Cretaceous period. It is evidenced by dinosaur fossils below the K-T boundary. The causes included increased volcanic activity and catastrophic events thus causing mass extinction of life.
Question 5: Describe the ways flood control management (levee systems). Oil company practices and urbanization combined to worsen the effects of Katrina.
The levee systems include the use of sand bags, portable inflatable tubes or hydrocrack to control floods along the river banks. They prevent the water from bursting the banks. The Oil Company and urbanization worsen the Katrina effects through pollution and degradation. This is usually done by dumping and oil spills in the water. Waste discharge, fertilizer run off and mining contribute a lot to Katrina effects.