Geology: Energy and Climate

THE SUN!!!!!

~15 million K^o

~6,000 K (about the same as Earth's core)

In electromagnetic energy (light energy) travels to Earth (takes about 8 minutes to reach us)

Nuclear Fusion constantly occurring in the sun. atoms weight slightly less after these nuclear reactions=this becomes energy released (E (energy) = m (mass) c (speed of light) ² )

(because it's exponential, even smaller atoms and reactions create a lot of energy)

proton-proton cycle, four hydrogen itoms combined to form helium atoms.

happen in central region of the sun because it is so hot.

this energy travels to the surface to make it out

sun goes through magnetic cycle, affects sunspots/radiation

sun has core, radiative, convective, photosphere, chronosphere, corona

atoms in internal of sun constant internal pressure, nuclear reactions keep it from collapsing into its own gravity

Total Solar Irradiance

energy arriving at the top of Earth's atmosphere from Sun

measured in Watts/M²

dark/cool spots on the surface (photosphere) of the sun caused by magnetic fields/distrubances

surrpunded by much brighter areas (facculae/solar flares)

more sunspot activity=brighter

yes; more sunspot activity means more irradience

however, this affect is not very drastic, miniscule

go through 11 year cycle of activity

(peaks every 11 years or so)

discovered by Schwabe

these peaks in sunspot activity have been linked with very minor increase in TSI, but not a lot

past few suncpot cycles have demonstrated downward trend

kind of:

taking into account earth's temperature, there has been a slight link with variation in temp and sunspot activity, but this activity is about -+.01%, hardly anything drastic.

additionally, sunspot activity in recent cycles have been on downward trend while the earth's temperature has been increasing, indicating that solar activity is not to blame for climate change

aspects of the cyles/relationships between Earth and the Sun

orbit shape changes from circular to more elliptic over time

these cycles take ~100,000 years

(ex: if earth started rotation in a perfect circle, it would take ~100,000 years to return to that perfect shape again)

distance from sun etc varies during orbit

tilt of earth on its axis

varies between 22.1^o-24.5^o

current tilt: 23.44°

cycle: ~40,000 years

earth's axis rotates

cycle: ~23,000 years

affects energy received at each pole

greenhouse gas

"bad" ozone at lower levels

highly reactive

Comes from:

biomass burning

car exhaust + sun energy

creates smog

big problem in low elevation cities

ex: los angeles

very bad for health

same chemical as troposphere O³ but in a different place

protects earth from Ultra Violet (UV) radiation

uv light dangerous to cell life

ozone layer shields earth; Earth's "sunscreen"

CFCs break down and react with ozone to make "hole" (thin patch) in ozone layer over antarctica.

no, in fact it actually has more of a potential cooling effect

the ozone layer usually absorbs the suns ultraviolet and traps infrared heat, heating the earth. but with the ozone hole, more heat is able to escape into space. the big problem is that

1. cfcs causing ozone depletion can fuel greenhouse gases and contribute to warming

2. this cooling effect would be less thatn 1/12th of the warming affect from greenhouse gases

The ozone hole itself has a minor cooling effect (about 2 percent of the warming effect of greenhouses gases) because ozone in the stratosphere absorbs heat radiated to space by gases in a lower layer of Earth’s atmosphere (the upper troposphere). The loss of ozone means slightly more heat can escape into space from that region.

Global warming is also predicted to have a modest impact on the Antarctic ozone hole. The chlorine gases in the lower stratosphere interact with tiny cloud particles that form at extremely cold temperatures — below -80 degrees Celsius (-112 degrees Fahrenheit). While greenhouse gases absorb heat at a relatively low altitudes and warm the surface, they actually cool the stratosphere. Near the South Pole, this cooling of the stratosphere results in an increase in polar stratospheric clouds, increasing the efficiency of chlorine release into reactive forms that can rapidly deplete ozone.

nitrogen: 78%

oxygen: 20.9%

argon: ~1%

other stuff: eztremely small amount

(CO2=.0407% or 407 PPM)

Parts per million

how we measure gases that make up an incredibly small percentage of our atmosphere

(like greenhouse gases like CO2, 407 ppm)

thermosphere (very thin)

mesosphere

stratosphere

troposphere (We are here)

chemicals that react with ozone layer, thin out, cause hole

from: plastic products, refrigerants, arosols

long lasting, hard to get rid of

contribute to greenhouse gas effects on global warming

CAUSES:

NATURAL

bacterial life in soil

microbial activity in oceans

HUMAN

agriculture (fertilization)

medicine (laughing gas)

arosol propellant

combustion engines

(U.S. N₂O emissions have been relatively stable but overall global emissions steadily rise)

Where:

lowest layer, up to ~10km above ground

Temperature:

temp decreases with higher altitude

most weather occurs here

Contains:

most weather

most water vapor

Etc: we are here

Where:

~10-50km above ground, 2nd up

Temperature:

inversion. caps convection (prevents air from rising much further)

higher=hotter

Contains:

ozone layer

some clouds in extreme temperatures above Antarctica, contribute to ozone hole

Etc:

because of temperature stratification (the higher=hotter) the air doesn't mix and leads to less turbulence. lack of vertical convection also means chemicals that get in can stay for a long time (eg CFCs)

Convection refers to the overturning and mixing of warmer and colder air layers.

The temperature structure of the stratosphere is one of warmer air over colder air. No, convection never occurs in the stratosphere because of this temperature structure.

gases which interfere with heat radiation

(put "blanket" around earth)

water vapor

carbon diocide (most abundent greenhouse gas)

methane

nitrous oxide

ozone

haloocarbons

known as a greenhouse gas since the 1800s

charles keeling

first who thought to mesure it: 1950s

keeling curve

measutinh co2 on a mountain in hawaii, found an upward trend

2022: 420 PPM

annnual wiggles in graph explained by seasonal variety

where coming from?

anthropogenic

fossili fuels, deforestation, etc

~10 gigatons/year

natural

volcanos etc

1/60th of anthropogenic output/year

upward trend, inconsistent rate

ANTHROPOGENIC:

energy

landfills

rice agriculture

biomass

cows (when kept in captivity and bred as they are, it's anthropogenic)

NATURAL

wetlands

termites

(50/50 between natural and anthro. maybe anthro 60 and natural 40. about there)

I>O = heating

O>I = cooling

I=O = balance

I-Input

O-output

X-Energy

t-Time

Δ-change

travels at the speed of light (in a vacuum)

shorter wavelenghts=greater energy

energy transported in PHOTONS

what we mostly get from sun: visible spectrum

what earth needs to get rid of to prevent heating: infrared

tiny packets of energy, absorbed by materials

emitted by the sun and travel to earth

"above violet" (after violet/visual spectrum on the electromagnetic spectrum)

absorbed by the ozone layer

"below red" (below red/visual spectrum)

absorbed in water and atmosphere (like CO²)

the spectrum emitted by a body depends on the temperature, this is what our sun emits

Mainly VISIBLE-obserbed at TOP of atmosphere and EQUATOR

the radiation is absorbed/disperses at differnt lattitudes and altitudes

infrared most radiation at sea level-

we lost radiation as it goes down because it is absorbed

Equator highest amount of radiation. further away from equator=disperse

~340 w/m²

_{^{(this is only 1/4th of TSI but that's because it's averaged across a planet that rotates, not all of it gets equal sun at once)}}

the top of the atmosphere at the equator

mostly infrared, less radiation than top of atmosphere