EPS 7 Midterm II

National Environmental Policy Act (NEPA) 1969

A 1969 U.S. federal act that mandates an environmental assessment of all projects involving federal money or federal permits.

Optical Depth (colors/wavelength)

A gas can be optically thick with respect to one wavelength (e.g. blue) while it is optically thin with respect to another (e.g. red)

Optical Depth (scattering and absorption)

A gas can be optically thick with respect to scattering, but optically thin with respect to absorption. Or vice versa. (scatters before it has a chance to absorb) (absorbs before it has a chance to scatter).

DDT

A powerful insecticide that is also poisonous to humans and animals; bioaccumulated and killed eggshells of raptor birds--eagles, peregrine falcons

How much of the burned carbon can be hidden as bicarbonate in the ocean from equilibration of the atmosphere and ocean?

About 60% On what timescale? 1,000 years Why is the timescale so long? The ocean is big. 1,000 years is roughly how long it takes the ocean's circulation to expose all of its water to the atmosphere

How much of the burned carbon is hidden as bicarbonate in the ocean after calcium-carbonate dissolution?

About 80% On what timescale? 10,000 years

1 ppm = 2 GtC

Adding 250 GtC to atmosphere brings from 280 ppm to 400 ppm

Negitive Forcings (atmosphere)

Aerosols -1w/m^2

What is the primary source of anthropogenic nitrous oxide?

Agriculture

Any evidence that silicate weathering created CaCO3 in the past?

All of the remaining carbon put into the atmosphere by humans is removed by silicate weathering On what timescale? 100,000 years

How much carbon has gone into the atmosphere and ocean

Atmosphere: originally 600 GtC, now 850 GtC (+250 GtC) Ocean: originally 40,000 GtC, now 40,150 GtC (+150 GtC)

Rachel Carson/Silent Spring (1962)

Book published that chronicles Rachel Carson's concerns about pesticides and environmental contamination--SPARKED ENVIRONMENTAL MOVEMENT

Coal

C or CH; comes from carboniferous (300 mya); fossilized peat

Which of these is an example of a halocarbon?

CF2Cl2

Oil

CH2; comes from jurassic (150 mya); fossilized plankton; formed in the tethys sea

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

CH4 + 2O2 → CO2 + 2H2O

gas

CH4; gas is overcooked oil

Amount of ocean carbon in different forms

CO2 + H2CO3, HCO3-, CO3--

Photosynthesis equation

CO2 + H2O + photon → O2 + CH2O

carbonate chemistry

CO2 + H2O ← → H2CO3 ← → H+ + HCO3- ← → 2H+ + CO3--

When permafrost thaws, it releases

CO2 and CH4

Positive Forcings (atmosphere)

CO2: +2w/m^2 Methane (CH4) + Nitrous Oxide (N20) + Ozone (O3) + Halocarbons = +1w/m^2

carbonate ion

CO3--

Calcium carbonate

CaCO3 sea shell, chalk, marble, snail shell, limestone, egg shell; Ocean acidification is a big deal for calcium carbonate (CaCO3); The more acidic the ocean, the more difficult it is for these species (and many others) to make their calcium-carbonate structures - coral, sea butterfly, sea urchin

After 1,000 years, what happens to the remaining 40% of burned carbon that is still in the atmosphere?

Calcium carbonate (CaCO3) dissolves from the ocean floor and on land, raising the pH, and allowing more CO2 to dissolve into the ocean. It does this by the carbonate grabbing an H+ ion. CaCO3 → Ca++ + CO3-- Ca++ + CO3-- + H+ → Ca++ + HCO3-

the world has used so far

Coal: 200 GtC Oil: 150 GtC Gas: 50 GtC Total of: 400 GtC

Originally there was

Coal: 5,000 GtC Oil: 350 GtC Gas: 250 GtC Land plants: 500 GtC Soils: 1,500 GtC Ocean: 40,000 GtC Atmosphere: 600 GtC

IPCC (Intergovernmental Panel on Climate Change) 1988

Created by WMO and UNEP

World Meteorological Organization (WMO)

First established in 1873, renamed in 1950 and becomes part of the UN--an organization is established to exchange weather data between countries

Four U.S. climate models

GISS (NASA) GFDL (NOAA) CESM (NSF) ACME (DOE)

Jules Charney

Gave first modern estimate of ECS; 1979 Charney report estimated 3 C increase.

hydrogen ion

H+

carbonic acid

H2CO3

Carbon cycle

H2O--> CH2O (plant matter)-->(photosynthesis)O2 -->(respiration) CO2

bicarbonate ion

HCO3- Bicarbonate is an electrically charged ion, so it cannot leave Carbon in the form of bicarbonate is hidden from the atmosphere

John Tyndall

Identified gases responsible for greenhouse effect: -N2, 02, Ar are transparent to infared -H20 (water vapor), CO2, CH4 are greenhouse gases Discovered T=1 at 5km

What is an acid?

It is a molecule that can give up an H+ ion

Things that are conserved

Mass: with units of kg Momentum: mass x velocity, with units of kg x m/s Energy: various forms, with units of kg x m^2/s^2 (=Joule)

Rayleigh scattering

Molecules redirect photons into a new direction. Short wavelengths (blue) are much more easily scattered than long wavelengths (red, infared): why the sky is blue

Ocean acidification in a nutshell

More CO2 in the air → more CO2 in the ocean → more carbonic acid → more acidic ocean

amount of ocean carbon in different forms

Most: HCO3- (bicorbante ion) Middle: CO3-- (carbonate ion) Least: CO2 + H2CO3

Why would the earth breathe with an annual cycle?

Much more land in northern hemisphere NH Summer: Plants grow-->photosynthesis > respiration-->CO2 is removed SH Winter: Plants do not grow--> respiration > photosynthesis--> CO2 is added

Which of these is an example of a NOx?

NO2

Respiration equation

O2 + CH2O → CO2 + H2O + photon

CO2 is removed from the atmosphere by three processes

Ocean acidification - 1,000 years Dissolution of CaCO3 - 10,000 years Silicate weathering - 100,000 years

RCP 6.0

Paris agreement

Stuff that can burn

Peat, Permafrost, Clatherates

Joseph Fourier

Postulated the greenhouse effect (1824); surface receives twice as much radiation from the atmosphere than from the sun--enhancement of solar radiation., START OF CLIMATE SCIENCE

RCPs (Representative Concentration Pathways)

RCP 2.6w/m^2, 4.5w/m^2, 6.0w/m^2, 8.5w/m^2; IPCC make plausible scenarios for the future of emissions (not predictions)

After 10,000 years, what happens to the remaining 20% of burned carbon that is still in the atmosphere?

Silicate rocks (CaSiO3) chemically weather in the presence of CO2 and make calcium carbonate (CaCO3) which locks up the C in new limestone CaSiO3 + CO2 → Ca++ + CO3-- + SiO2 → CaCO3 + SiO2 Land rocks exposed to rainwater with dissolved CO2 Ions carried to the ocean in rivers Carbon locked away as new calcium carbonate on the ocean floor

In between trasnparent and opaque

T"="1

Transparent

T<<1

When does a gas emit to space

T=1; at each increment in T (tau) the gas behaves like the surface of a solid body

Opaque

T>>1

What does pH measure?

The concentration of H+ ions in the water, Lower pH is more H+

Bicarbonate is an electrically charged ion, so it cannot leave Carbon in the form of bicarbonate is hidden from the atmosphere

The ocean hides away most of the carbon that dissolves into it

climate sensitivity

The response of the climate system to a given radiative forcing

Parallel Computing

The simultaneous execution of the same task on multiple processors to obtain results faster.

What is acidic water?

Water with a lot of H+ ions in it

grid cells

Weather and climate models discretize the world into boxes

Higher Optical depth

You can get a higher optical depth between two locations by increasing the distance Or by increasing the density (e.g., by increasing the amount of greenhouse gases for longwave absorption and emission)

Global warming is caused by

a decrease in outgowing power, not an increase in incoming power --> positive forcing

Planck feedback (negative)

a negative feedback loop when the planet is warmer: --> more T^4 longwave emission --> cooling tendency

middle clouds

altostratus, altocumulus

Advanced Microwave Sounding Unit (AMSU)

antenna that picks up microwave signals emitted by earth's atmosphere; polar-orbiting satellite.Sun-synchronous: ascend and descend . over the equator at the same time each day and night.

Each increment in Tau

at each increment (T=1, T=2, T=3, T=4) the gas behaves like the surface of a solid body

Gya

billion years ago

RCP 8.5

business as usual

Doubling of CO2

causes 3k increase in global temp.

feedback parameter

change in net inflow per change in stock

Climate sensitivity is the

change in temperature for a doubling of CO2

High clouds

cirrus, cirrostratus, cirrocumulus

Total feedback in uncertain because

cloud feedback is uncertain--why ECS could be from 1.5 k to 4.5 k

Mie Scattering

clouds scatter light; cloud drops are bigger than N2 molecules--no wavelength preference; clouds are white.

Three types of fossil fuels

coal (C or CH), oil (CH2), natural gas (CH4)

FIngerprint of a CO2-induced global warming

cooling in stratoshpere, warming in lower atmosphere/surface (10km)

negative forcing

decrease stock; decrease spigot flow

Svante Arrhenius (1896)

determined that humans could create greenhouse effect by burning fossil fuels (1896)

Feedback

extra flow out (in excess of steady-state flow) response of flows to the perturbation

perturbation

extra water in tank (in excess of steady-state stock) Current stock - stock in original steady state

Conservation laws

fundamental principles of physics that tell us that certain things are neither created nor destroyed.

James Hansen (1988)

gave congressional testimony about global warming in 1988

Cirrus

hair

cumulus

heap

positive forcing

increase stock; increase spigot flow

ΔT=kpΔz

k=some constant (depends on gas and wavelength or light; big k for greenhouse gases and longwave) p=Density of the gas p Δz=distance

stratus

layer

The first forecasts

made by the Smithsonian in D.C. in 1857

supercomputer

made up of individual computers no more special than your laptop. A supercomputer is "super" because it is made of thousands or millions of computers wired together for parallel computing.

Dave keeling (1960s)

measurements of CO2 at Mauna Loa; first unambiguous evidence of rising CO2

alto

middle

Mya

million years ago

An extra molecule of CH4 in the atmosphere causes an extra molecule of CO2 in the atmosphere

more warming than

lapse rate feedback (negative)

negative feedback when the planet is warmer: --> lapse rate descreases -->T=1 emission layer warms faster than surface --> T=1 layer emits even more longwave --> cooling tendency

Vertical Clouds

nimbostratus, cumulonimbus

Peat

of the 1500 GtC in soil, peat accounts for 200 GtC; peat is made in swamps

nimbo

percipitation

WHat is the layer of the sun that emits light

photosphere

In summer

photosynthesis > respiration

water vapor feedback (positive)

positive feedback when the planet is warmer: --> air holds more water vapor (clausius-clapeyron) --> more greenhouse gas (water vapor) --> warming tendency

cloud feedback (positive)

positive feedback when the planet is warmer: --> fewer clouds -->lower albedo --> more sunlight absorbed -->warming tendency

Ice feedback (positive)

positive feedback when the planet is warmer: -->less ice and snow -->lower albedo -->more sunlight absorbed -->warming tendency

borehole temperatures

prove an increase of about 1K from preindutrial temperatures. Prof. Lonnie thompson from tOSU works on this.

Doubling CO2 (w/m^2)

radiative forcing of 3w/m^2

in winter

respiration > photosynthesis

Shortwave (in the atmosphere)

some scattering, but very little absorption and emission

surface-air thermometers

stevenson screen is an enclosed thermnometer that shades and ventilates; designed by thomas stevenson in 1864.

low clouds

stratus, stratocumulus, cumulus

positive feedback

tends to increase size of perturbation make the rich richer and the poor poorer (e.g. interest in a bank account)

nagative feedback

tends to reduce size of perturbation make the rich poorer and the poor richer (e.g. psychology)

Kya

thousand years ago

timescale

time for something to get mostly done

Evidence of warming

tropical glaciers, borehole temperatures, surface-air thermometers, satellites

Longwave (in the atmosphere)

very little scattering, but a lot of absorption and emission

Equlibrium climate sensitivity (ECS)

we wait until earth equilibrates (~100 years) to new CO2 level before differencing the mean temps. 1.5 C-4.5 C 3k

Which way do storms move in the continental United States?

west to east

RCP 2.6

wildly optimistic

Buys Ballot

(1872) Proposes an international network of stations in Europe

Final Perturbation = Forcing / |feedback parameter|

(only for negative feedback parameters!)

Total atmospheric forcing

+2w/m^2

Total feedback parameter

-1w/m^2/K

Serial computing

1 core processor completes one task before computing another. One cycle at a time

clathrate--methane clathrate

1,000-10,000 GtC; a compound in which molecules of methane are physically trapped within the crystal structure of water. As planet warms, clathrates release methane.

Land Warming

1.5x that of projected global mean warming

Current global emissions of CO2

10 GtC/ year; emissions double every 23 years; americans emit 4x as much CO2 than global avg; CO2 is rising 2ppm/year; pop. will rise to 11 billion in 2100

how much does atmospheric CO2 increase each year?

10 GtC: 5 GtC to atmosphere (+2.5 ppm), 5 GtC to ocean

Methane in the atmosphere oxidizes to CO2 on what timescale?

10 years

big bang; earth formed

14 gya; 4.5 gya

Clean Air Act 1970

1970 -- nixon

Environmental protection agency 1970

1970 -- nixon

United Nation Environmental Programme (UNEP) 1972

1972

Clean Water Act 1972

1972 --veto overridden

Endangered Species Act 1973

1973--nixon

first assessmnet report of IPCC

1990 working group I: Physical science working group II: Adaptation working group III: mitigation

IPCC released 5 assessment reports

1990, 1995, 2001, 2007, 2014; summarize state of science--do not generate new science-- 4000 pages with ~800 authors

Atmosphereic temp.

200K-300K

preindustrial CO2 concentration

280 ppm; first 280 ppm + 3k, 2nd + 1.8k, 3rd + 1.2k

How much has berkeley's temp increased?

2k; 3-4 F

What is the current radiative forcing from the extra CO2 that is currently in the atmosphere?

2w/m^2

With RCP w/m^2

2w/m^2 = ~ 1 K of warming at 2100, but will equal the same if we wait enough

How much does a person use of coal, oil, and gas?

3 tons of coal, 22 barrels of oil, and 2400 m^3 of natural gas)

Permafrost

350 GtC of 1500 GtC in soil permanently frozen layer of soil beneath the surface of the ground; topped by an active layer that freezes and thaws every year.Permfrost decays and emits CO2. Over all depths permafrost contains 1500 GtC

Space Temp.

3K

Earth's climate sensitivity

3K because: doubling of CO2 causes +3w/m^2and e a r t h' s feedback parameter is -1w/m^2/K final perturbation = forcing/|feedback parameter| =(3w/m^2)/|-1w/m^2/K| =3K!

Where is T=1

5 km in atmosphere