Test 2 prep questions: Unit 4 Flashcards
What is the role of the sun, atmosphere, ocean, water, and land surface in the Earth’s climate system?
Sun: Emits solar radiation that heats the Earth
-Sets in motion the circulation patterns of the atmosphere and ocean which influences weather systems
Atmosphere:
-The protective blanket
-Screens out the sun’s harmful ultraviolet rays
-Storehouse for gases and particles
-Affects climate and weather systems
Oceans:
-Helps to distribute heat around the world by moving tropical water towards the poles, and returning cool water back to the equator
-Moderates the climate of coastal areas
Water:
-Helps to cool the surface (evaporation)
-Reflects the sun’s energy (clouds/ice caps)
-Keeps the Earth warm (water vapour)
-Absorbs solar radiation
Land:
-Affects the flow of air currents and the formation of weather systems because it heats and cools more quickly than water
-Bright areas are reflective of the sun’s energy
-Dark areas absorb the sun’s energy (trees for photosynthesis)
-Vegetation and soils are important in the hydrological cycle and the movement of greenhouse gases in and out of the atmosphere
What is albedo and why is it an important factor in evaluating the temperature on the planet?
Albedo is a measure of the reflectivity of the Earth’s surfaces
Lower albedo results in more heat being absorbed which increases the temperature of the planet
What is a heat island?
An area that is significantly warmer than its surrounding rural areas due to human activities
Describe the Earth’s energy budget comparing the path of incoming energy and outgoing energy
Incoming
-48% net solar energy absorbed at the surface
Outgoing
-25% as evaporation
-5% as convection
-17% as net thermal radiation
Explain the role of the atmosphere and the oceans in distributing heat around the planet and how each of these functions
Atmosphere: Convective currents
-Warm air at the equator rises, and cooler air at the poles descends which creates air currents that circulate air throughout the globe.
How it works:
1. The sun heats the ground which heats the air above it
2. Warm less dense air rises
3. Rising air cools, radiates heat to the atmosphere, and becomes dense forming clouds and precipitation
4. Air is pushed to low pressure areas
5. Cool dense air sinks to low pressure area on surface
Ocean: Ocean Conveyer belt
-Driven by temperature and salinity differences
How it works:
Warm, less salty water near the surface flows towards the poles. As this water cools and becomes saltier (due to evaporation and freezing), it becomes denser and sinks.
This sinking water flows towards the equator, forming deep currents. Eventually, these deep currents rise to the surface, completing the cycle.
Explain the natural and cultural greenhouse effect and contributing gases.
Greenhouse gas effect: When solar radiation passes through the atmosphere, some of the infrared radiation is absorbed and re-emitted by greenhouse gases. The cultural greenhouse effect occurs because we are emitting for of the GHGs and producing new ones which is trapping more infrared radiation and creating a blanket effect
Natural GHGs raise the temperature about?
35 degrees celsius
Compare the relative strengths of CFCS (chlorofluorocarbons), methane, and nitrous oxide, in contrast with CO2
- Methane is 25x more powerful than CO2
- Nitrous oxide is 300x more powerful than CO2
- CFC’s are up to 10000x more potent than CO2
Explain how scientists are able to evaluate the geological record of atmospheric conditions with modern measurements. What are the conclusions forthcoming from this evaluation?
Through vostok ice cores. They trap gases and can be extracted for analysis
-3600 meter core equates to 400 000 years ago
Conclusion:
-Results in positive radiative forcing: a net increase in energy and temperature because of the energy imbalance from what’s coming in and what’s leaving (>4 degrees celsius annually)
-The peaks used to cap at 300 million parts per million, now it’s at 400 million
-When CO2 is plotted with temperature there is a strong correlation over 4 cycles. Peaks = volcanic activity, pits = glaciation
Explain the impacts of arctic amplification as it relates to sea ice, Greenland ice sheet, and permafrost soils.
How will this affect all aspects of our lives in the near future?
Sea ice:
-reduction in albedo
-positive feedback: lower albedo= more sunlight absorbed=snow and ice melting
-older and thicker ice is thinning
-more water is absorbing heat, less is being reflected
Greenland ice sheet: land based ice sheets
-Melting is causing sea levels to rise (by 2mm), and the ocean conveyer speed is declining due to a reduction in the density gradient (reduced ocean circulation)
Permafrost:
-Melting of ice in deep soils causes soils to collapse, increased production on CO2 and methane
-Increase in the active layer
Results:
Sea ice: Higher temperatures in the arctic
Greenland: Europe is colder, fish production is reduced
Permafrost: Widespread warming of the planet due to increased CO2 and methane
-Land slumping
-Soil erosion
Overall:
-Droughts
-Change in rain and snow patterns
-Melting glaciers and thawing permafrost
-Warmer oceans and rising sea levels
-Agriculture productivity increase at higher latitudes and decrease in lower altitudes
-Increased irrigation
-Reliance on pesticide application
-Human health risks
What are the short waves and long waves?
Short wave: Ultraviolet, X-ray, Gamma ray
-Incoming radiation
-screened by the atmosphere
-can cause change to exposed organisms
Long wave: Infrared
-Outgoing radiation
Is methane evenly spread out or does it have hot spots?
Hot spots
What are the atmospheric layers essential to life? How do you distinguish between the layers?
- Troposphere
-Temperature decreases with increasing altitude
-Weather, wind, storms, and clouds
-“bad” ozone layer
-Where we dump our fossil fuels - Stratosphere
-Temperature increases with increasing altitude because of UV radiation by ozone layer that heats the air
-Commercial jets fly here
-Contains “good” ozone layer that absorbs UV radiation - Mesosphere
-Temperatures are at the lowest (-138 degrees celsius)
-Meteors burn up from friction with air molecules - Thermosphere
-Temperature increases to 1000 degrees celsius or more
-Important in long-distance communication because it reflects outgoing radiowaves back to earth without satellites
-Auroras occur here
-Gases absorb short-wave radiation here
Can tell between the layers depending on when the temperature changes
The variability in the exposure to incoming solar radiation depends on?
The curvature and angle of incoming radiation that differs between equator and poles, thickness of the atmosphere, Earth’s tilt.
What is the albedo of cities, grass, bare sand, oceans, forests, snow, and clouds absorb?
City: 10-15%
Grass: 15-20%
Bare sand: 30-60%
Oceans: 5%
Forests: 5%
Snow: 80-90%
Clouds: 50-55%
Are greenhouse gases naturally occurring or man-made?
Which are which?
Both
Man made: Ozone, Halocarbons (contain fluorine, chlorine, bromine) ex. Chlorofluorocarbon/hexafluoride
Natural: Water vapour, carbon dioxide, methane, nitrous oxide
What are the largest contributors to natural warming?
Water vapour(65%) and CO2(25%)
Other (10%)
The rapid warming in the arctic is associated with?
Albedo
-less reflection, more absorption
