Geology 310T Exam 1 Questions and Answers Graded A

Geology 310T Exam 1 Questions and Answers Graded A The Earth is being - Altered by humans We call this influence - Anthropogenic Examples of anthropogenic influences Pollution, deforestation, urban heat islands, animal extinction, changing water flow, melting ice, ocean acidification Keeling Curve Graph that plots the ongoing change of CO2 concentration in Earth's atmosphere. It shows the life cycle of trees "breathing" in small squiggly oscillations. Keeling Curve is evidence for - Global warming Ozone depletion is evidence for - The ozone hole Deforestation is evidence for - Loss of biodiversity Do people in California live where the water is? No The rate of change is - Unprecedented, especially CO2 Weight analogy If you gained 30 pounds over a year, that would be less noticeable than if you gained 30 pounds in one day. It's the same for environmental change Rate of Change calculation Y axis/X axis or change in temp/time Why do we care? Crises are global Crises are complex, they involve complex systems Parts of the Earth System 1. Atmosphere- gas 2. Hydrosphere- liquid 3. Biosphere- organic 4. Cryosphere- solid liquid (ice) 5. Lithosphere/geosphere- solid How much of world ecosystem services have been depleted? 60% Of 24 evaluated ecosystems, how many have been damaged? 15 Species extinction is how much past the normal rate? 100-1000 times Crises are complex because of - Responses and feedbacks Feedback- a self perpetuating mechanism of change and a response to that change. We often assume feedbacks are linear (easy to predict), but they are usually - Non-linear and complex (hard to predict) Why are climate change issues so contentious? They involve the global economy and money, and they impact our core beliefs and worldview. The past is... The key to the present/future What drives earth's climate system? Solar energy (THE SUN) Why are the poles colder than the equator? 1. Earth's shape and available energy per unit area 2. More energy reflected at higher latitude 3. Thicker atmosphere at equator, BUT more scatter of energy at high latitude 4. Higher albedo at higher latitude If energy was not redistributed, what would happen? The poles would get colder and the equator would get warmer. This redistribution of energy, the process that regulates Earth's temperature, is known as: Earth's energy budget. What comes in must equal what goes out. More solar energy is available per unit area - At the equator The poles are cooler than the equator because - They are at a different angle to the sun, not because they are further away How is Earth's energy circulated? The ocean and the atmosphere. Temperature differences create pressure differences. Pressure gradient force Created by temperature differences, move air/water from high to low pressure. What does the circulation of temperature resemble? A lava lamp 3 circulation cells Hadley cell, Ferrell cell, and Polar cell ITCZ Inter-Tropical Convergence Zone (thermal equator) What drives oceanic circulation? Atmospheric circulation, but the ocean is constrained by basins What is a system? An entity composed of diverse but interrelated parts that function as a complex whole What is a state? A set of important attributes that characterize a system at a particular time States that are not in transition are referred to as - Equilibrium states What causes a system's state to change? Forcing or perturbation Forcing A sustained input of energy into a system, progressively changes the system. I.e. adding CO2 to the atmosphere (man-made) or insolation (natural) Perturbation A short lived input of energy into a system, system reverts back. I.e. A volcanic eruption What are the parts of a system called? Components What are the links between components? Couplings. They allow for the flow of information (energy) Positive couplings Amplify change, positive feedback Negative couplings Reduce change, negative feedback What determines the Earth's temperature? - Solar radiation - Atmospheric warming - Albedo Earth's temperature assuming blackbody radiation -18 degrees Celsius What is blackbody radiation? Something that emits or absorbs EMR with 100% efficiency, none lost EMR Electromagnetic Radiation. A stream of photons that move in waves at different energy levels Visible light ROYGBIV, with R being the slowest waves and V being the fastest What part of the EMR spectrum do humans see in? 0.4 - 0.7 Planck Function The distribution of wavelengths emitted by something is dependent on the body's absolute temperature Wein's Law λ ≈ 2898/T (temperature) The flux of radiation emitted by a blackbody reaches its peak value at wavelength max (inverse to the body's absolute temperature) Earth and Sun temperature Earth: 288 degrees K Sun: 5780 degrees K Which gives off a wider range of EMR, the Sun or the Earth? The sun, by like a lot How much warming does the Greenhouse Effect account for? +33 degrees C What is the Earth's average temperature with the GHE? 15 degrees C Main gases in Earth's atmosphere Nitrogen 78% Oxygen 21% Argon .9% Water vapor .00001% CO2 .037% The most common gas in the Earth's atmosphere is - Nitrogen What is a good definition for a greenhouse gas? A gas that effectively absorbs and emits infrared radiation (IR) Is water vapor an excellent greenhouse gas? Yes 3 most important greenhouse gases Water vapor H2O Carbon dioxide CO2 Methane CH4 Insolation INcoming SOLar radiATION How do we learn about past climate? - Use archives like tree rings, ice cores, lake sediment, ocean sediment, cave deposits - These contain information about temperature, volcanism, chemistry, vegetation - Determined using rings/layers. Thicker rings = more moisture How does the GHE work? Smaller waves of radiation can get into the atmosphere but cannot get out as larger waves and become trapped Anthropogenic - Caused by humans. Global warming is unnatural enhancement of the greenhouse effect and is anthropogenic Possible causes for global warming and their likelihood: Trace gases (greenhouse gases added by humans): Very likely Urbanization (only taking temperatures in human inhabited areas): Very unlikely. Temps are taken all over, not just in urban centers Solar variability: Unlikely Volcanism: Very unlikely (no long term effect) Natural climate cycles: Unlikely The California Water Crisis Population goes up, use and waste goes up, water availability goes down.