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ATMS 11 1 Test 1 With
Complete Solution
What factors influence climate? - ANSWER 1. Sunshine (Latitude)
- Topography/Mountains
- Proximity to Oceans and Large Lakes
- Ocean Currents
- Presence of Trees/Vegetation
- Greenhouse Gases
What does a thin atmosphere mean? - ANSWER We can change atmospheric condition.
_____ of the mass of the atmosphere is within _____ of the surface. - ANSWER 90%; 16km
CO2 increase on Keeling Curve is Human-Induced. _____ due to fossil fuel burning. _____ due to deforestation. - ANSWER 90%; 10%
What is the current rate of increase of CO2? - ANSWER 100-1000 times faster than nature can change CO2.
We're over ____ ppm now. - ANSWER 410
What do greenhouse gases do? - ANSWER Greenhouse gases slow heat loss to space.
It's warmed about ____ in the last 130 years. - ANSWER 1 degree C
Where has it warmed the most? - ANSWER Northern High Latitudes
______ has warmed more than ______. - ANSWER Land; Ocean
What else is happening? - ANSWER 1. Arctic sea ice is melting.
- The ocean is gaining heat.
- Sea level is rising (20 cm = 8 in).
- Glaciers are melting.
- Humidity is increasing.
- Species are shifting.
What is a fundamental uncertainty? - ANSWER Future human behavior
Where is there uncertainty? - ANSWER Uncertainty in both human behavior and climate feedbacks.
How does light interact with matter? Absorption example? - ANSWER Matter absorbs light and gains internal energy.
Asphalt heating up on a hot day.
Reflection example? - ANSWER Matter reflects (scatters) light without gaining or losing energy.
Clouds, ice, aerosol particles
Transmission example? - ANSWER Light passes through matter unimpeded.
Sunlight through a glass window.
What type's of electromagnetic radiation are important for Earth's energy
What in the atmosphere behaves like this? - ANSWER CLOUDS
Material: Glass
Does it block visible light? - ANSWER NO
Material: Glass
Does it block IR light? - ANSWER YES
Material: Glass
What in the atmosphere behaves like this? - ANSWER GREENHOUSE GASES
Trash bag is ______ to visible, but ______ to IR. - ANSWER opaque; transparent
Glass is _______ to visible, but ______ to IR. - ANSWER transparent; opaque
Cardboard is ______ to both visible and IR. - ANSWER opaque
Visible light has a _______ frequency, a _______ wavelength, and is ________ energetic than IR light. - ANSWER higher; shorter; more
Radiative energy balance with an atmosphere includes _____. - ANSWER The greenhouse effect
Greenhouse gases causes the outgoing radiation to happen at higher levels (no longer from the surface). Air gets much colder as you go upward. What does this tell us about the radiation? - ANSWER Radiation to space is much less (colder -> less emission).
What is radiative balance? - ANSWER Ein=Eout.
What is a forcing? What are its units? - ANSWER Change in shortwave in or longwave out; directly impacts temperature; W/m^
What is a feedback? - ANSWER Response to change in forcing; indirectly impacts temperature
Positive Feedback: Amplifies original forcing
Negative Feedback: Weakens original forcing
Desertification - the transition to a desert region changes the albedo of Earth. What kind of forcing is this? - ANSWER Negative Forcing, Shortwave
The atmosphere cools significantly, decreasing the moisture in the atmosphere. What kind of feedback is this? - ANSWER Positive Feedback, Longwave
CO2 and other GHGs cause the atmosphere to warm increasing the amount of moisture in the atmosphere. Since water vapor is a greenhouse gas, this leads to more warming? - ANSWER Positive Feedback; Longwave
It's hot outside. Your body temperature rises. What is this? - ANSWER Positive forcing
You begin to sweat. Your body temperature falls. What is this? - ANSWER Negative feedback
Undergrad comes back to school. The bus becomes less crowded. What is this? - ANSWER Positive forcing
Why do dry climates have more extreme temperatures than wet climates? - ANSWER Daytime - Evaporation cools hot days.
Nighttime - Water vapor greenhouse effect traps heat
Since the 1970s, coal power plants have been required to reduce their emission of air pollutants such as sulfate aerosols. This is a ________ on the climate system which acts via the aerosol direct effect. - ANSWER positive forcing
What can reflect shortwave radiation back into space? - ANSWER Clouds, Earth's surface, Aerosols, Ice, Dust, Deserts, Snow, Pollution
Passing an international policy that substantially reduced the amount of aerosols put into the atmosphere likely lead to an increase in global temperatures. - ANSWER True, because aerosols reflect solar radiation and contribute to cloud brightening, so reducing them increases Ein.
What are examples of shortwave forcings? - ANSWER Changes in sun's strength, changes in surface albedo, volcanic emissions, aerosols, air pollution
Does climate sensitivity depend on forcings, feedbacks, or both? - ANSWER
Feedbacks
What is the urban heat island effect? - ANSWER Buildings and pavement absorb and re-emit longwave radiation which warms the urban area.
Why are most of the deserts located around 30N or 30S? - ANSWER Sinking motion
How does energy arrive from the sun? - ANSWER Energy from the sun is radiation. It goes through space at the speed of light and is absorbed or reflected once it gets back to earth.
What kind of radiation does the sun emit? - ANSWER Visible light and near-infrared (infrared with very short wavelength) radiation and a small amount of UV radiation
These three bands are called shortwave radiation.
How strong is the sun? - ANSWER By the time it gets to the top of earth's atmosphere, the Sun shines at a strength of 1366 W/m^2 (what's experienced in the tropics when the sun is directly overhead).
______ is by the atmosphere - ANSWER 30%; 20%; 5%; 5%
What is albedo? - ANSWER Fraction of incident light that's reflected away
Ranges from 0 (low albedo - no reflection) to 1 (high albedo - all reflection)
Things that are white tend to reflect more.
Darker things absorb more radiation.
Clouds, ice, and snow all have _____ albedos. Cloud albedos range from _____ to ______. Thicker clouds have a _____ albedo. - ANSWER high; 0.2 to 0.7; higher (reflect more)
Snow has an albedo ranging from ____ to _____. - ANSWER 0.4 to 0.
Ice's albedo is approximately ______. - ANSWER 0.
Ocean's Albedo - ANSWER <.
Forest's Albedo - ANSWER.
Desert's Albedo - ANSWER 0.
Total absorbed radiation is _____ of the incoming solar radiation. - ANSWER 70% = 240 W/m^
How does the earth lose energy? - ANSWER Infrared (longwave) radiation
________ temperatures means ____ energetic radiation. - ANSWER Higher; more
Sun emits _______ radiation.
Earth emits ____ radiation. - ANSWER shortwave; longwave
If the energy into the system is greater than the energy out, the temperature will __________. - ANSWER increase
A temperature increase then results in an increase in temperature _____. This will happen until Ein = Eout which is called ________. - ANSWER out; energy balance
If the solar radiation into Earth is greater than the outgoing longwave radiation, the temperature will _______. A temperature increase then results in
What contributes to the fact that high latitudes (near the poles) are colder than the tropics (near the equator)? - ANSWER The sun's rays hit the surface at a shallower angle in the high latitudes, so the same amount of radiation is spread out over a larger surface area.
What greenhouse gas has a large fraction of its anthropogenic source from livestock? - ANSWER Methane
When the surface temperature of a blackbody increases, the energy emitted _________, and the wavelength at which maximum radiation is emitted shifts to ______ wavelengths. - ANSWER increases; shorter
In the year 2100, what is the difference in the expected concentration of CO with and without an international agreement? - ANSWER 420 ppm
What are some examples of climate forcings? - ANSWER Volcanic eruption, deforestation, increased greenhouse gases, the solar cycle
After a volcano erupts, the Earth cools. In response, ocean waters freeze causing the Earth's albedo to increase, which further cools the Earth. This series of events is an example of a _________ forcing and a ________ feedback. - ANSWER negative; positive
What are three ingredients needed to make a cloud? - ANSWER Moisture, particles, pressure or temperature change
Consider a hypothetical situation where there is an increase in the number of particles inside the bottle but the amount of water vapor stays the same. Due to the aerosol indirect effect, how will the properties of the cloud change? - ANSWER Smaller cloud droplets will form and the cloud will reflect more shortwave radiation.
How might we have expected daytime temperatures in New York and Pittsburgh to change during a dust storm? - ANSWER Colder temperatures resulting from dust reflecting shortwave radiation
Which two factors are most important for the toll a heat wave will have on people? - ANSWER Duration and nighttime lows
What is true about sea ice melt? - ANSWER Affects weather systems (changing global heat transport)
Contributes to erosion
Amplifies global warming through the ice-albedo effect
Does NOT contribute to sea level rise
Recent increases in methane likely due to: - ANSWER fossil fuel leakage
What factors affect flooding? - ANSWER Deforestation
Urbanization
Soil Erosion
Land Use
How do shifts in rising motion significantly affect precipitation? - ANSWER Leads to uncertainty in forecasts
Key to most dramatic changes that have been observed
Sahel Drought: Drying of Lake Chad
Southern Hemisphere storm tracks shifting poleward
To get rain, you need moist air and rising motion. Globally, the rainy regions are where air is rising. Where is the ITCZ? - ANSWER Over warm water in the tropics (where hot air rises)
Where do monsoons occur? - ANSWER Over certain land surfaces in the summer
What are examples of land areas that will dry out (more evaporation into the
warmer air)? - ANSWER Subtropics: SW US, Southern Europe, Southern Africa/Australia
Warmer air can hold more water vapor. This means: - ANSWER Rainy places will get rainier
Downpours will become stronger
Where do deserts occur? - ANSWER Where air is sinking
Away from storm tracks
Mostly in the subtropics
What are some effects of global warming? - ANSWER Shifting the distribution of temperature towards hotter everywhere
More likely: Hot Extremes
Less likely: Cold Extremes
Many land areas are expected to dry out (will experience more intense dry heat during the day time)
More greenhouse gases mean hotter nights in places that don't dry out
What is the urban heat island effect? - ANSWER Strongest at night
Caused by buildings keeping longwave radiation in and materials staying hot
Developing countries are lower
Per economic output emissions - ANSWER US is below average on list
In the US, __________ and ______ are the main sources of CO2. - ANSWER Electricity and transportation
What are the main sources globally for CO2 equivalent? - ANSWER Industry, electricity, transportation, agriculture
Emission Sources of CO2 - ANSWER 90% fossil fuels (oil and coal)
10% deforestation
Positive feedbacks lead to amplification of a forcing. Negative feedbacks lead to ______ temperature change for a given forcing. - ANSWER less
Ice-albedo feedback is a _________ feedback. Ice/snow melts with increasing temperature which lowers albedo. - ANSWER positive
Cloud feedbacks are the most uncertain feedbacks. Feedbacks roughly _______ the amount of expected warming. - ANSWER double
Examples of Shortwave Forcings - ANSWER Soot on Snow (positive)
Land cover changes (negative forcing in total; clearing low-albedo forests leads to more reflection)
Changes in strength of the Sun; correlated with sun spot cycle (solar variability 0.2 W/m^2 peak to peak)
Aerosols are the most important shortwave forcing from air pollution (small particles in the air); strong cooling influence w/ uncertainty (-0.8W/m^2); caused global dimming
Climate forcings are measured by radiative forcings. Longwave forcings are: - ANSWER greenhouse gases (except water vapor)
Current CO2 radiative forcing:
Total greenhouse gas radiative forcing: - ANSWER 1.68W/m^2 and rising
3 W/m^
Forcing is measured as the change in __________ radiation due to the gas at fixed temperature. - ANSWER longwave
CFCs = _____ of anthropogenic greenhouse effect - ANSWER 6%
