Week 14: Climate Science

 

1. The big question addressed in lab, and a description of what you did.
1. We started out lab by discussing climate change and where we are at now. We then discussed the greenhouse effect-visible light comes in, some is reflected as infrared, infrared can escape to space, most heat is contained in the atmosphere. Snow reflects a lot of the light, without snow, less gets reflected. A big question is what is the albedo effect and how does it affect climate? How does the GH Effect interact with the albedo effect? Is the albedo effect a positive or negative feedback loop? Positive cycles amplify while negative cycles negate effects. Ice caps melting at the North Pole are a positive feedback loop (increasing absorption rates). Greenhouse gas is a gas that absorbs and re-emits infrared light. For centuries, atmospheric carbon dioxide has never been above 300 ppm, but currently averaging 418 ppm (and isn't slowing down or tapering off). Since 1750-- carbon dioxide has increase 42%, methane has increased 157% increase, Nitrous Oxide 25% increase. 
2. A description of what you learned in Thursday's lecture.
1. In lecture, we engaged in a discussion with Julia and Katie about climate change. We had the opportunity to ask questions to climate scientists.
3. Answer questions about the weekly textbook reading:
   1. What did you learn?
   1. The atmosphere is relatively small, only about 60 miles wide. The atmosphere lets heat in from the Sun so that the Earth is livable but also blocks the Sun's harmful radiation. The atmosphere is a key part of regulating temperature, weather, and climate. Greenhouse gases let sunlight through to reach the surface of the Earth and then trap its heat in the atmosphere. Greenhouses gases have complex asymmetrical shape and vibrate. They absorb infrared radiation from the sun and the radiation is released back to the atmosphere and keep the planet warm. When infrared radiation from the Sun reaches the Earth, some radiation is reflected back into space with a high albedo (ice) and other radiation is absorbed by greenhouse gases and surfaces with a low albedo. When there are too many greenhouse gases in the atmosphere, they radiate more heat than normal. Albedo is the amount of energy reflected by a surface. Light surfaces tend to have high albedo because they reflect more energy and dark surfaces tend to have a low albedo because they absorb more energy. Currently Earth's albedo is decreasing because of climate change (positive feedback loop). Carbon is an abundant element critical for life on Earth. It moves naturally between the atmosphere, land, and water. Scientists use data from ice cores to create climate models which can help predict future climate change.
   2. What was most helpful?
   1. The video was most helpful in explaining the greenhouse effect.
   3. What do you need more information on?
   1. I still need more information on what exactly greenhouse gasses are and how it affects climate change.
   4. What questions/concerns/comments do you have?
   1. How can an individual person reduce carbon emissions?