# How things work college course/Global warming quizzes
## Hints
### How things work college course/Global warming quiz 1: Lede

click to expand quiz 1 hints :
Point added for a correct answer:
Points for an incorrect answer:
Ignore the questions' coefficients:
1
The lede's graph of the "Global Land Ocean Temperature Index (1880-2013)" shows little or no temperature rise over the last ____ years pause bewteen 2000 and 2010
30
3
100
10 * See figure
300
2
Since 1971, 90% of earth's increased energy caused by global warming has been stored in the _____________, mostly _____________
sea; in the top kilometer *Thermal energy is absorbed on Earth. It's easy to guess that more is absorbed by the larger oceans, and that it takes time for the heat to penetrate to the bottom. The suprise is the 90% figure, but you aren't asked about that. Easy question!
sea; in the bottom kilometer
land; near the poles
land; near the equators
air; in the water vapor
3
The lede's graph of the "Global Land Ocean Temperature Index (1880-2013)" shows that since 1920, there has never been a decade of overall cooling
true
false *See the graph above: A decade of cooling starting circa 1940
4
The largest temperature increases (from 2000-2009) have occurred
on the ocean surface
near the poles * Why do the poles heat up more? See nasa.gov suggests the main reason is that snow is white and tends to reflect the sun's energy. As the snowline retreats up north, more energy is absorbed. Also, perhaps, the increase in storms is circulating the air more, making the Earth's temperature more uniform.
near the equator
in the western hemisphere
5
The 2007 IPCC report stated that most global warming was likely being caused by increasing concentrations of greenhouse gases produced by human activities. Among the science academies of the major industrialized nations, this finding was recognized by
90% of the academies of science
all of the academies of science *There should be no controversy over whether the Earth is warming, or even what is causing it. The question should only regard the level of urgency. UNLESS, you think virtually all the top scientists are wrong (which does occasionally happen)
all but the US academy of science
60% of the academies of science
6
in 2013, the IPCC stated that the largest driver of global warming is carbon dioxide (CO2) emissions from fossil fuel combustion. Other important sources of CO2 are
population growth and waste disposal
cement production and waste disposal
cement production and land use changes *The trick is to remember: LAND USE: trees absorb CO2 and emit oxygen
population growth
7
The lede's graphs of the "Global Land Ocean Temperature Index (1880-2013)" indicates that from 1960 to 2012 the average temperature increased by approximately
16° Celsius
0.6° Celsius *Just remember 2 degrees C per century, the time interval is about 50 years or half a century. I will write 2C/century on the board during the test if you ask me. I want you to THINK, not memorize
0.06° Celsius
0.16° Celsius
1.6° Celsius
8
Which statement is FALSE about the lede's map of the temperature anomaly (2000-2009)?
all portions of Antarctica have warmed *Look at map
Northern Asia has warmed more than southern Asia
Central Europe has warmed more than the continental United States
The United States has warmed more than Australia
9
The lede's "CO2 Emissions per Year" graph (1990-2010) shows dips and rises that are caused by changes in
worldwide efforts to curtail emissions
the earth's distance from the sun
the sun's energy output
the world economy *Easy to guess this one: The world economy determines how much energy we use. Wealth and energy consumption are strongly corrolated among the nation.
10
The lede's "CO2 Emissions per Year" graph (1990-2010) shows solid straight lines that represent
estimates made in the year 2000 of what would happen in the future * the only answer that makes sense
estimates of the contributions from everything except fossil fuels
estimates of the contributions from fossil fuels alone
estimates of the impact on land temperatures
11
In climate science, mitigation refers to:
climate engineering
adaptation to the effects of global warming
reduction of green house emissions *To mitigate is to reduce. In some countries, being drunk can reduce or lessen the guilt or blame of a violent act (but not in the USA)
building systems resilient to the effects of global warming
12
Anthropogenic means something that
humans can repair
human caused *Anthropology=study of humans. Generate is to cause
humans cannot repair
will hurt humans :

### How things work college course/Global warming quiz 2: Observed temperature changes

Hints 2 :
Point added for a correct answer:
Points for an incorrect answer:
Ignore the questions' coefficients:
1
The Earth's average surface temperature rose by approximately _______ per decade over the period 1906–2005.
7.0°C
0.7°C
0.07°C * No need to memorize, you will have the graph during the test and we will review how to do the calculation in class
2
In the twentieth century, the rate of earth's average temperature rise was closest to
0.7 °C per decade
0.7 °C per year
0.7 °C per century * No need to memorize, you will have the graph during the test and we will review how to do the calculation in class
3
Compared with the first half of the twentieth century, the rate of earth's average temperature rise during the second (latter) half was
half as much
about the same
twice as much * No need to memorize, you will have the graph during the test and we will review how to do the calculation in class
4
Compared with the second half of the twentieth century, the rate of earth's average temperature rise during the first half was
twice as much
half as much * No need to memorize, you will have the graph during the test and we will review how to do the calculation in class
about the same
5
The urban heat island effect refers to the fact that urban areas tend to be hotter than rural areas. The urban heat island effect is estimated to account for approximately _____ of the temperature rise over the past century.
0%
30%
0.3%
3% * Just remember that it is a small effect, but not extremely small. This effect involves the fact that more measurements are now made in cities than in the countryside.
6
Proxy temperatures measurements are defined as indirect inferences gathered from ice cores, tree rings, and so forth
true *: See wikt:proxy server, wikt:proxy war, and wikt:proxy
false
7
Proxy temperatures measurements are defined as measurements made using measurements from space.
true
false *: See wikt:proxy server, wikt:proxy war, and wikt:proxy
8
The Reconstructed Temperature (0-2000 AD) plot in "Observed Temperature Changes" shows temperature measurements. The solid black line represents
tree proxy measurements
thermometer measurements * "Reconstructed refers to proxies and the Hockeystick graph. We discussed this wikt:Ad nauseam in class
the Little Ice Age
the Medieval Warming Period
a 10 year average
9
The Reconstructed Temperature (0-2000 AD) plot in "Observed Temperature Changes" shows temperature measurements, as well as what curious feature? (See also Divergence problem)
the Little Ice Age being less prominent than the Medieval Warming period
a divergence between the tree and pollen proxy measurements
a tiny gap at the end of the proxy measurements * wikt:Ad nauseam or wikt:Ad nauseam (without italics? You use italics whenever you want to emphasize that this is a Latin phrase or if people are not likely to know what it means.
the fact that the different proxy measurements deviate considerably from the average of all proxy measurements
10
A rise in the sea level is associated with global warming because
ice and snow melts
both of these are true * Most substances expand when heated. We will do an exception in lab (rubber bands)
water tends to expand as it warms
11
What happens when water is heated?
it expands at temperatures below 3.98°C and contracts above 3.98°C
it expands at temperatures above 3.98°C and contracts below 3.98°C * This is logical: Water shrinks when cooled, but expands when it freezes to ice. There must be a transition somewhere!
it absorbs CO2
12
No direct method exists that permits an independent measurement of the heat content of the oceans, other than the fact that the air is warming
true
false * I forget why this is true, perhaps it is because we can measure the ocean temperatures?
13
Ocean temperatures are increasing more slowly than land temperatures because oceans have more heat capacity and because evaporation cools the water.
true * Yes, both mechanisms are at work here. When you heat metal on the stove it quickly gets hot, more heat also has to go into water to change the temperature by one degree. And, evaporation releases heat from a fluid
false
14
Ocean temperatures are increasing more slowly than land temperatures because the oceans are absorbing less heat energy from the sun
true
false * No, 90% of the sun's energy (that is absorbed) goes into the oceans (top region) :

### How things work college course/Global warming quiz 3: Initial causes of temperature changes and external forcings

Hints 3 :
Point added for a correct answer:
Points for an incorrect answer:
Ignore the questions' coefficients:
1
The "Greenhouse effect schematic" in the section on "Temperature changes..." indicates that most of the energy from the Sun is absorbed by the earth's atmosphere.
true
false *: already discussed, 90% of energy goes into top layer of ocean. Don't forget to distinguish between HEAT (energy) and TEMPERATURE (what a thermometer measures)
2
The "Greenhouse effect schematic" in the section on "Temperature changes..." indicates that most of the energy from the Sun is absorbed at the earth's surface.
true *: already discussed, 90% of energy goes into top layer of ocean. Don't forget to distinguish between HEAT (energy) and TEMPERATURE (what a thermometer measures)
false
3
Which external force plays the smallest role in current efforts to model global warming?
greenhouse gasses
solar luminosity (i.e. variations in energy from the sun)
volcanic eruptions
orbital cycles *This is the weakest, over 200,000 years or so this might be important in the ice age cycles
4
"External forcings" refer to effects that can increase, but not decrease, the Earth's temperature.
true
false * See w:Climate_change#External_forcing_mechanisms and Climate_change#Internal_forcing_mechanisms. The latter refers to (1)Ocean/Atomosphere variability and (2) Life. Everything else is external. This is a stupid definition that you should forget after taking this class IMHO.
5
"External forcings" refer to effects that can either increase or decrease, the Earth's temperature.
true
false *** I will delete this from the quiz (you all get it right). This might be a typo. In class (if you ask) I will remind you that forcings can either increase or decrease the temperature.
6
Water vapor contributes more to the greenhouse effect than does carbon dioxide.
true * Surprise to the non-expert (that scientists have been aware of for years). See "feedback" in later portions of this exam
false
7
Carbon dioxide contributes more to the greenhouse effect than does water vapor.
true
false * Surprise to the non-expert (that scientists have been aware of for years). See "feedback" in later portions of this exam. Note how I put the true/false question in in both directions.
8
The Keeling curve shows that carbon dioxide concentrations
show a steady rise in CO2 levels, with increasing slope, and regular and predictable annual fluctuations *: The predictable fluctuations mostly involve ocean plankton cycles
show a steady rise in CO2 levels, at constant slope, and regular and predictable annual fluctuations
show a steady rise in CO2 levels, at constant slope, and irregular fluctuations due associated with El Ninos and La Ninas.
9
The climate change community is divided between those who believe the goal should be to eliminate the earth's greenhouse effect altogether, and those who argue that we should attempt to minimize earth's greenhouse effect.
true
false *: No sane person thinks we can or should eliminate the earth's greenhouse effect. As we will see after the test, a little greenhouse effect has always been present on Earth and we would be very uncomfortable (freezing cold) without it
10
Emissions scenarios are
estimates of changes in future emission levels of greenhouse gases * Easy to remember: Scenario is a prediction, and humans dominate how these emissions will change in the future
estimates of how greenhouse gasses are absorbed and emitted by nature
estimates of how greenhouse gasses are absorbed and emitted by the world's oceans
estimates of how greenhouse gasses are absorbed and emitted by agriculture
11
It is expected that carbon emissions will begin to diminish in the 21st century as fossil fuel reserves begin to dwindle.
true
false *: The scientists were wrong in the 1960s about the end of the "carbon age" in which humans burned coal and oil and natural gas for energy. What they missed was the way technology would allow us to use sound to map the earth underground and find more oil
12
The carbon cycle
is a proposal to trade carbon credits.
describes how carbon is absorbed and emitted by the oceans, soil, plants, etc. *: See w:Carbon cycle
is an effort to store carbon in underground caves.
13
Global dimming, caused by air-born particulates produced by volcanoes and human made pollutants
exerts a heating effect by absorbing infra-red radiation from earth's surface
is more related to the ozone problem than to global warming
exerts a cooling effect by increasing the reflection of incoming sunlight *Remember this: dark "soot" on the snow warms the polar regions, but in the air it prevents light from reaching Earth and acts to cool
14
Soot tends to warm the earth when it accumulates in atmospheric brown clouds.
true
false*Remember this: dark "soot" on the snow warms the polar regions, but in the air it prevents light from reaching Earth and acts to cool
15
Soot tends to cool the earth when it accumulates in atmospheric brown clouds.
true*Remember this: dark "soot" on the snow warms the polar regions, but in the air it prevents light from reaching Earth and acts to cool
false
16
In the arctic, soot tends to cool the earth.
true
false*Remember this: dark "soot" on the snow warms the polar regions, but in the air it prevents light from reaching Earth and acts to cool
17
In the arctic, soot tends to warm the earth.
true*Remember this: dark "soot" on the snow warms the polar regions, but in the air it prevents light from reaching Earth and acts to cool
false
18
Approximately what percent of global warming can be attributed to a long-term trend (since 1978) in the sun's energy?
50%
0% *The energy output from the Sun fluctuates slightly but can be completely ruled out because the fluctations are cyclical and the correlations are easy to measure. A rare case where the "extreme" (zero) answer is correct.
10%
30%
19
Greenhouse warming acts to cool the stratosphere
true * Surprizingly true: The stratosphere is the stable atmosphere where passenger jets fly. It is getting colder because the CO2 below that layer acts as a blanket to block the Earth's infra-red (heat) radiation. The Sun doesn't heat this part because there are no clouds and little water vapor: the rays pass right through it. You instructor considers this an important reason for believing in global warming: Adding blankets to a sleeping person cool the top layer of the top blanket
false
20
Greenhouse warming acts to warm the stratosphere
true * See above
false
21
The distinction between the urban heat island effect and land use changes is that the latter involves the earth's average temperature while the former involves only the temperature near weather stations where the measurements are made
true * See wikipedia:Urban heat island
false
22
Depleting the ozone layer cools the stratosphere because ozone allows UV radiation to penetrate.
true
false * The ozone layer heats the stratosphere by absorbing ultra-violet radiation, which is also good for us because UV radiation causes skin cancer
23
Depleting the ozone layer cools the stratosphere because ozone absorbs UV energy from the sun that heats the stratosphere.
true * TYPO will be deleted from test: should have been "warms" instead of "cools"
false :

### How things work college course/Global warming quiz 4: Feedback and climate models

Hints 4 :
Point added for a correct answer:
Points for an incorrect answer:
Ignore the questions' coefficients:
1
Changes in ice-albedo refers to changes in
how much CO2 is absorbed by the sun
how much the Earth's surface absorbs or reflects incoming sunlight *Latin root: albus means white as in albino (person with no skin color) and albedo (astronomy) and albumen (egg white).
how much ice is melted during the summer months
2
The Stefan-Boltzmann law plays a central role in establishing a planets temperature as the sun heats the planet until the thermal (infra-red) radiation away the planet rises to match the solar radiation onto the planet P=σAT$^4$
true *:See figure: It will show that an OVER-SIMPLISTIC model allows one to calculate the temperature of any planet if the greenhouse effect is ignored.
false
3
The Stefan-Boltzmann law plays a central role in establishing a planets temperature as the sun heats the planet with thermal (infra-red) radiation adding to the other solar radiation onto the planet
true
false *:See figure: The Sun is in the center and emits visible light (shown as yellow). The red planets are equadistant from the Sun and emit IR (infra-red) light (shown as red).
4
Stefan-Boltzmann radiation is called a negative feedback mechanism because if the sun's radiation increases, the Stefan-Boltzmann law ensures that more heat is lost from the planet to compensate.
true *:See figure: The dotted lines describe cones of energy coming from the Sun. The big planet gets four times the energy from the Sun, but emits 4 times the IR (at the same temperature) because it has twice the radius as the smaller planet.
false
5
Stefan-Boltzmann radiation is called a negative feedback mechanism because if the sun's radiation increases, the Stefan-Boltzmann law ensures that this heat is retained by the planet.
true
false *:See figure. Stefan-Boltzmann radiation balance law is not a feedback effect.
6
Computer models accurately model feedback mechanisms associated with the role of clouds as a feedback mechanism.positive acoustical feedback gets out of control
true
false *:Clouds are really hard to model ... it's the "weather"!
7
Computer models accurately model feedback mechanisms associated with how the soil will retain or release CO2 as the earth warms.
true
false *:Another problem with long range projections: Life is hard to model
8
Analysis of the uncertainties associated with feedback suggests that the "worst-case" scenario is easier to model.
true
false * Worst case scenarios are the most difficult to model: What are the chances that A and B occur, but that the hoped for B does not?
9
Analysis of the uncertainties associated with feedback suggests that the "worst-case" scenario is more difficult to model.
true * Worst case scenarios are the most difficult to model: What are the chances that A and B occur, but that the hoped for B does not?
false
10
The cryosphere refers to
the north and south poles
the upper atmosphere
the highest mountains
two of these are true * Anywhere on the surface of the earth that is cold: mountain peaks and the poles
11
While computer modeling indicate that the warming since 1970 is dominated by man-made greenhouse gas emissions, they are unable to conclusively ascertain whether the warming from 1910 to 1945 was anthropogenic.
true *: Apparently its the factor of two increase that has them convinced
false
12
Computer modeling has conclusively established that anthropogenic warming has occurred since 1910.
true
false *: See previous question
13
How is the validity of a computer model typically tested?
by verifying its ability to calculate past climate conditions.
all of these are true *Without all three ways to test them, it would be unwise to trust computer models
by verifying its ability to calculate current climate conditions.
by making predictions about future years and seeing if they come true. :

## Links

* How to use testbank
* Quizbank
* Wikipedia:Global warming