EPS 7 Midterm 2 Review

what is the radiative forcing of the other positive forcings combined?

+1 W/m2

what is the radiative forcing of CO2?

+2 W/m2

how much will the average American use of fossil fuels each year?

- 3 tons of coal - 2400 cubic meters of gas - 22 barrels of oil

what were the preindustrial levels of carbon?

- atmosphere: 600 GtC - land/plants: 500 GtC - soils: 1500 GtC - ocean: 40,000 GtC

what are the underground concentration carbon?

- coal (5000 GtC) - gas (250 GtC) - oil (350 GtC)

what are the three fossil fuels?

- coal (C or CH) - oil (CH2) - gas (CH4)

what have we used of the underground concentration?

- coal: 200 GtC burned - oil: 150 GtC burned - gas: 50 GtC burned

why is global warming a positive forcing (aka net inflow increases)?

- higher CO2 causes a higher altitude of T =1 surface emitting to space - since atmosphere has lapse rate of 6.5 K/km, its colder higher up - by SB law, a colder T = 1 surface radiates away less power => holds in more radiation

what are things conserved?

- mass (kg) - momentum (kg x m/s) - energy (kg x m2/s2 or J)

what is the total feedback parameter given all the feedbacks?

-1 W/m2/K

middle clouds

-altostratus: middle layers -altocumulus: middle heaps

high clouds

-cirrus: hair like -cirrostratus: hair like layers -cirrocumulus: hair like heaps

clouds w/ vertical development

-nimbostratus: layer of precipitation -cumulonimbus: heap of precipitation

low clouds

-stratus: layer (you can't see the sun but theres no wetness from precipitation) -stratocumulus: layer of heaps -cumulus: regular ass cloud

who owns climate models in the US?

1) NASA 2) NOAA 3) NCAR 4) DOE

why is climate sensitivity defined in terms of doubling?

1) a doubling is convenient 2) each doubling gives roughly same amount of warming

what are the three things that can burn that contribute to positive feedback?

1) peat 2) permafrost 3) clathrates

how does the atmosphere interact with radiation?

1) scatters some shortwave 2) aborbs and emits longwave

what are the four signs of warming?

1) tropical glaciers 2) borehole temperature 3) surface-air thermometers 4) satellites

what is the current global emission of CO2?

10 GtC/year (5 into ocean, 5 into atmosphere)

methane in the atmosphere oxidizes to CO2 on what timescale?

10 years

what is the timescale of hiding carbon for the dissolution of CaCO3?

10,000 years (to hide 80% of burned carbon)

what is the timescale of hiding carbon from silicate weathering?

100,000 years (for the remainder)

in a business-as-usual scenario, what is a likely concentration of atmospheric CO2 in the year 2100?

1000 ppm

what is the timescale of carbon hiding by ocean acidification?

1000 years (to hide 60% of burned carbon)

what is the likely amount of carbon contained in methane clathrates?

1000-10000 GtC

ff we hold the concentrations of greenhouse gases constant at the levels anticipated in 2100 for the RCP8.5 scenario, roughly how much land warming would we get if we waited long enough?

12 K

when did the Big Bang occur?

14 Gya (billion years)

when was oil formed from the Jurassic?

150 Mya (million years)

in what year was the greenhouse effect postulated, thereby initiating the field of climate science?

1824

1 ppm

2 GtC

roughly at what rate is the atmospheric concentration of CO2 increasing?

2.5 ppm/year

the carbon contained in peat down to 1 meter is equivalent to how many years of fossil-fuel burning at the current rate of emissions?

20

how much carbon is there in peat worldwide down to one-meter depth?

200 GtC

where does the burning of fossil fuels go?

250 GtC to atmosphere, 150 GtC to ocean

what was the preindustrial concentration of carbon dioxide?

280 ppm

how much has Berkeley warmed?

2K

whats the radiative forcing for a doubling of CO2?

3 W/m2

when was Earth formed?

3.5 Gya (billion years)

how much is in one GtC (gigaton) of carbon?

3.7 Gt of CO2

when was coal formed from carboniferous?

300 Mya (million years)

when did fossil fuels from organism form?

300-500 Mya (million years)

If we hold the concentrations of greenhouse gases constant at the levels anticipated in 2100 for the RCP4.5 scenario, roughly how much globally averaged warming would we get if we waited long enough?

4 K

how much fossil fuel have humans burned?

400 GtC

what is the current concentration of atmospheric CO2?

400 ppm

If we hold the concentrations of greenhouse gases constant at the levels anticipated in 2100 for the RCP4.5 scenario, roughly how much land warming would we get if we waited long enough?

6 K

If we hold the concentrations of greenhouse gases constant at the levels anticipated in 2100 for the RCP8.5 scenario, roughly how much globally averaged warming would we get if we waited long enough?

8 K

if a sand dune's feedback parameter is −20 kg/s/m, by what amount does its net rate of inflow change if we apply a sudden height perturbation of −4 m?

80 kg/s - because sudden height perturbation = final perturbation

given Earth's feedback parameter of -1 W/m2/K, what is roughly its final temperature perturbation in response to a brightening of the Sun that leads to 9 W/m2 of extra solar absorption?

9 K

what chemical formula most accurately describes the burning of natural gas?

CH4 + 2O2 → CO2 + 2H2O

when permafrost thaws, it releases

CO2 and CH4

which is not a contributing factor to the seasonal cycle in atmospheric CO2?

CO2 is a greenhouse gas

what happens in ocean acidification?

CO2 is added, reacting with H2O to make H2CO3 (carbonic acid) -H2CO3 will give up a H+ ion to make HCO3- (bicarbonate ion) - HCO3 gives up its H+ to created CO3-- (carbonate ion)

which compounds have positive forcings?

CO2, CH4, N2O, O3, halocarbons

what happens in dissolution of CaCO3?

CaCO3 dissolves and increases pH, allowing more carbon to dissolve

what chemical reaction ultimately removes the excess carbon from the atmosphere and ocean?

CaSiO3 + CO2 → CaCO3 + SiO2

which chemical reaction describes ocean acidification?

H2CO3 → H+ + HCO3−

which are greenhouse gases?

H2O, CO2, CH4 (opaque)

which are not greenhouse gases?

N2 and O2 (transparent)

aresols

NOT aersol, but a suspension of fire solid/liquid droplets in air - volcanic ash, pollen, sea salt, soot - decrease Earth's albedo, which decreases absorption of radiation

who first predicted global warming and made a calculation of Earth's climate sensitivity in 1896?

Syvante Arrhenius

how deep into a gas does the gas emit radiation like a solid surface?

T = 1

who was the IPCC founded by?

WMO and UNEP in 1988; first repot in 1990

what is methane clathrate?

a crystallized lattice structure of water with CH4 molecules trapped in between

advanced microwave sound unit (AMSU)

a fancy atenna that picks up microwaves from Earth's atenna - flys in a polar orbit -measures the T = 1 layer by k

how much coal have we used?

a few percent

how much warming do boreholes show?

about 1 K from preindustrial

which compounds have negative forcings?

aersols

stock

amount of stuff in container

lapse rate feedback

as Earth warms, the lapse rate changes, causing the T = 1 level to warm faster => increases longwave emission - there's a cooling effect - negative feedback

water vapor feedback

as earth warms, air holds more water vapor, decreasing longwave emission - causes more greenhouse gases - positive feedback

what is earth's climate senstivity?

averaging 3K, but can be 1.5-4.5K

what happens in silicate weathering?

basically weathers rocks to produce CaCO3 that gets flushed into oceans

why are clouds white?

because all wavelengths are scattered equally

why the is the Sun orange?

because light was not scattered (longwaves)

why is the sky blue?

because shortwave radiation is scattered (aka blue wavelengths)

why are we not worried about CO2 emissions from the ocean?

because the carbon dioxide in the ocean is dissolved

why is the Northern Hemisphere more important?

because there is more land, so the cycle of photosynthesis and respiration are more based on the northern hemisphere

halocarbons

carbon atom with atom from halogen element (Cl and Fl) - used as a refrigerant in air conditioning and used to be in hairspray - mainly stoped using bc it depletes ozone

CH4

caused by livestock burps, landfills, rice paddies, and fugitive natural gas (leaky) - causes more radiative forcing than CO2, but eventually becomes CO2

optical depth equation

change in T = kp X change in z

what does it depend on?

change in T= kp X change in z - k = constant (depends on the gas and wavelength of light) - p = density - z = distance

feedback parameter

change in net inflow per change in stock; tells us how much net infow changes for a given perturbation

what makes earth's climate sensitivity uncertain (predicted at 3 K but can really be 1.5-4.5 K)?

clouds

which of the following carbon pools has the largest amount of carbon at present?

coal

pH

concentration of H+ ions in a solution

ozone (O3)

created from NOx (NO and NO2) and VOCs (volatile organic compounds) - think smog

Joseph Fourier

created the heat equation; credited with postulating the existence of a greenhouse effect and thereby kicking off the field of climate science

John Tyndall

discovered greenhouse gases - found that there were gases that were transparent, but that others were opaque and could absorb and hold longwave radiation

when is warming the greatest?

during the initial warming, since warming amounts decrease with time

what is climate sensitivity aka?

equilibrium climate sensitivity, because we wait for Earth to equilibriate to a new CO2 level

what does respiration do with carbon?

expels it with water vapor

forcing

externally applied change in a flow, specifically net inflow - negative: external reduction - positive: external increase

perturbation

extra stuff (in excess of steady state flow); change in stock - can be positive (more) or negative (less) stock than usual

final perturbation

forcing/feedback parameter - only applies to negative feedback systems (aka only stable systems, so not sand dunes)

coal

fossilized peat (swamp soil) that is compressed to the point where it dries out, depleting it of oxygen and leaving carbon

oil

fossilized plankton that is compressed at high pressures and temps

conservation laws

fundamental principles that tell us that certain things are neither created nor destroyed; no exceptions!

Jules Charney

gave the first modern estimate of earth's climate senstivity

how much oil have we used?

half

how does ocean hide carbon?

hides it through bicarbonate ion (HCO3-), but that makes ocean more acidic bc of more H+

optically thick

if some amount of gas is opaque to radiation (aka does not allow passing)

optically thin

if some amount of gas is transparent to radiation (allows passing)

T = 1

in between transparent and opaque; right where gas goes thin to thick

is Earth in a steady state?

in preindustrial yes because the flow in of sun's energy equaled flow out of radiation, but right now NO

if the atmosphere does absorb/emit longwave radiation

infrared thermometer reports 200-300K - when it doesn't, it reports 3K

flows

inputs or outputs for a container of stuff

what does photosynthesis do with carbon?

intakes it to create oxygen and glucose

IPCC

intergovernmental panel on climate change

what makes Earth different from Mars and Mercury?

it has an atmosphere

if a sand dune's feedback parameter is +8 kg/s/m, what happens if we suddenly reduce the height of the dune by 2 m?

it will disappear

if a sand dune's feedback parameter is −5 kg/s/m, what happens if we suddenly add 4 m of sand?

it will go back to steady state bc we add stock

Planck's feedback

largest negative feedback system - more longwave emission that goes out has a cooling effect by SB law

with a negative feedback system, forcing

leads to a new steady state; reestablishes equilibrium - if the earth warms, it will cool - if the earth cools, it will warm

cloud feedback

less clouds has lower albedo, so more sunlight is absorbed and warms - positive feedback

ice feedback

less ice and snow causes lower albedo, which causes more sunlight to be absorbed - positive feedback

how do greenhouse gases work? what is the greenhouse effect?

lets shortwave in, but traps that energy by slowing longwave emission and collective cooling - basically traps longwave from escaping

longwave

little scattering, but a lot of absorption and emission

Charles David (Dave) Keeling

made scientists aware of global warming because of measurements at Mauna Koa in 1953

acid

molecule adding H+ ions to water

which of the following is a violation of conservation of mass/momentum/energy?

nothing

static equilibrium

nothing is happening

optical depth

opacity in T (tau)

T > 1

opaque (optically thick)

gas

overcooked oil

what is scotch made from?

peat

what do we call the layer of the Sun that emits light to space?

photosphere

what occurs more in the summer?

photosynthesis

infared thermometer

power per area in infrared radiation emitted by an object you point at it - calculates T by PPA

nitrous oxide (N2O)

primarily the result from fertilizers, but also used as a propellant and as laughing gas

Luke Howard

published paper in 1803 that we use to classify clouds today

what occurs more in the winter?

respiration

what do stevenson screen measurements show?

show an increase in surface air temps (and collectively across locations too) through min and max temps

what book is credited with kicking off the U.S. environmental movement in 1962?

silent spring by rachel carson

shortwave

some scattering, but very little absorption and emission

what do IPCC assessments do?

summarize the state of climate science

what happens with each doubling?

the amount of warning gets smaller, but still increases

climate sensitivity

the change in mean global temp for a doubling of atmospheric CO2

what motivated the formation of the International Meteorological Organization, later renamed the World Meteorological Organization, in the 1800s?

the desire for weather knowledge, large storms for Europe, and telegraph

why does burning fossil fuels cause global warming?

the extra atmospheric CO2 lifts the τ = 1 layer to a colder level in the atmosphere

the higher the k and/or ρ of some gas in the atmosphere...

the higher the effective height emission to space

how can we use borehole temps to show warming?

the more you descend in boreholes, the more sampling you get from thousands of years ago. upper layers are warmer than they should've been

global warming

the response of Earth's steady-state heat budget to a positive forcing from extra greenhouse gases in the atmosphere -decrease of radiation flow out (bc radiation is being held)

the higher the density (p)...

the shorter the distance change in Z to get to T =1 - today, the density of greenhouse gases is increasing, so we get to T =1 faster

feedback

the system's natural change in inflows in response to a perturbation; positive amplifies the perturbation, while negative dampens the perturbation

timescale

the time it takes something to get mostly done

what is the active layer?

the top layer of permafrost that thaws out

when there is a geometric increase in CO2

there is a linear increase in temp

what is happening to the glaciers?

they are disappearing

supercomputer

thousands and millions of computers wired together for parallel computing

steady state

total flow in = total flow out

T < 1

transparent (optically thin)

stevenson screen

used for surface air temp measurements; enclosure that shades and ventilates, as well as reflect away sunlight

what does AMSU show?

warming at low altitudes and cooling at high altitudes

what is the reality if we keep going?

we will more than double but less than quadruple our CO2 ppm

grid cells

weather and climate models discretize the world into boxes

serial computing

when a single computer solves a single problem

why is ocean acidification bad?

when acid increases, it blocks the production of CaCo3, which harms animals w CaCo3 structures (coral, sea butterfly, sea urchin)

parallel computing

when multiple computers solve a single problem

negative feedback

when there is a decrease in perturbation size; males steady state possible

positive feedback

when there is an increase in perturbation size

James Hansen

woke the public to global warming in 1988