GLOBAL CLIMATE CHANGE FINAL

A P P M C

Archean Protozoic Paleozoic Mesozoic Cenozoic

Paleozoic

542 - 252.2 MYA

Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, Permian

Mesozoic

65.5 - 252.2 MYA

Triassic, Jurassic, Cretaceous

Cenozoic

65.5 - 0 MYA

Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene, Holocene

Hadean

4 Billion Years ago, earth coalesces: meteorite showers protoplanet names Theia making Earth bigger and gives us a big ol moon. Makes earths orbit oblique

Causes of Climate

Galactic, Orbital Variations, Solar magnetic dynamics (sunspot)

Cosine law (angle of interception)

Energy absorption is inversely related to the angle of interception (area of interception INCREASES with angle)

Largely responsible for differences in seasonal temp / precip

More atmosphere solar energy passes through

Kepler's Second Law

The earth requires the same amount of time to orbit the sun, irrespective or orbital variations. When the orbit is eccentric orbital velocity varies (faster when closer slower farther away)

Inverse Square Law

Force/Power declined with distance.

Increasing the distance from the sun distributes energy across a broader surface area - energy interception decreases non-linearly with distance

Obliquity

The angle of earth to the sun (relative to the poles) changes over time meaning the energy interception also changes. 41kya oscillations

Alters energetics according to the cosine law

Eccentricity

Shape of earths orbit relative to the perfect circle.

Changes over time, alters distance to the sun

~100kya cycles INVERSE SQUARE LAW

KEPLERS SECOND AS WELL

Procession

The relationship between the two, in particular the timing of the solstices relative to the timing and degree or orbital variations. Aphelion - furthest to the sun. Perhelion - closest to the sun

Summer/winter solstice align almost perfect

Current CO2

~415 ppm which is 125 ppm above historical known maximums

Misinformation regarding sunspots

Magnetic field variations in the sun drive changes in sunspots 11 year cycles. Although they emit less EM, increases brightness overall. Corresponds with irradiance BUT the temperature does not follow these trends

Cyclone storms

Low pressure systems rotate perpendicular to earths rotation due to Corialis forces. Anticyclonic high pressure dry storms like the Santa Anna winds - build up in inland deserts.

Increase temp increases evap and atmospheric H2O - latent heat capacity

Not making more storms but making them worse

Heating effects: Ice Sheets

Melting ice sheets mean influx of very cold low salinity water into the ocean. El nino (SW wet) / La Nina (S dry). Shallow ocean temps in the equitorial Pacific influence high pressure ridging off the CA coast. Lower global albedo - possibly more clouds which increase albedo (land retains heat more so positive feedback )

CO2 levels are increasing and we can point to the burning of fossil fuels as the source due to

 Atmospheric C13 is diluted by burning fossil fuels depleted in C13, indicating an increase in CO2 levels from anthropogenic sources.

 how should the amount of O18 accumulation in ice cores at mid latitudes change with decreasing temperature

The O18 content in ice formed in temperate glaciers will decline

What is the mechanism that allows us to estimate past climate from oxygen 18 (O18)

As a heavier isotope, its concentration in long-term reservoirs such as ice and sediments increases with increasing temperature

 the effect of increased absorbance of electromagnetic radiation (EM) has the following effect

 The average wavelength of emitted EM becomes shorter

Global circulation model (GCMs)

Global Climate Models (GCMs) began by mapping water movements, later expanding to climate explanations due to linked water and air dynamics. They integrate physical forces, conservation laws, grid-based dynamics, and variable forcings, and are validated with temperature records. Fluid mechanics are central. Key concepts include Newton's Second Law (F=MA), Coriolis force, conservation of motion, and the First Law of Thermodynamics. Without greenhouse gases, Earth would be a "snowball." Models require sensible questions and parameters to avoid flawed outputs.

IPCC (International Panel on Climate Change)

• a wildly successful scientific endeavor

• 1) Translation of expert knowledge into lay terms

• 2) Build capacity to lay audiences to understand and interact with the science

• 3) Create international expertise– the capacity to act based on the report

4) Consensus is a top down approach, and “nobody likes being told what to do”

Least to most GHG, climate forecasts

• SSP1-1.9: most optimistic 1-1.5 degree warming

• SSP1-2.6:

• SSP2-4.5 (we are currently 4.2)

• SSP3-7.0

SSP5-8.5: most fossil fuels burn, we don’t know if we can reach this

Climate change impacts to sea life is likely associated with changes in productivity

• Less ice = less phytoplankton = less krill = less large organisms

• Corals - a group of animals that create distinct structures out of CaCO₃ 

  • CO₂ into water makes carbonic acid which acidifies the water → dissolved their CaCO₃ structures. 

  • Increase the temperature, these poikilotherms can die 

  • Fundamental and realized niche increase in size for stingrays when the temperatures get higher in the ocean

Amphibians: catastrophic losses on land

• Decline is global and rapid

• Many formerly common species have essentially disappeared

• Poikilotherms are very sensitive to temp changes

• For frogs, the invasive chytridiomycosis can rapidly drive species to extinction

• Humans are safe from most fungal diseases due to our hot body temp - common fungal diseases only live on the edge of our skin

• Amphibians eat many insects so insect population can boom

Consumption/Prod

Consumption: US - 19.89, Saudi Arabia - 3.35, China - 14.76, India - 4.76

Production: US - 20.21, Saudi Arabia - 12.14, China - 5.12, India - n/a

Transport GHG

World: 33%

US: 19% - 10% personal transit

KEY POINTS

• Most GHG emissions originate from electricity generation

• Emissions are dominated by oil, coal, and natural gas, that is, transit and electricity

• Biofuels: GHG savings is minimal, and maybe even more costly in the long-term due to depleted soil resources

Coal

1. Coal power generation is nearing max expected efficiency while coal power generation is increasing overall. 

2. Produces lots of GHGs (CO₂, NO_x, SO_x (acid rain))

3. Unlike natural gas, coal-fired plants produce much additional pollutants

4. Pollution is worse in 1st gen plants, which are common in china

5. Radioactive release is ~100 times higher around coal burning plants than nuclear reactors (radioactive isotopes in coal)

Natural gas

Natural gas is increasingly important source of power generation

California electricity generation sources

1. CA has one of the most diverse electricity generation portfolios!!

2. Lots of wind and solar, productive geothermal wells, well developed hydropower infrastructure

3. Also thank policies which have focused on non-fossil fuels

4. We have not had a coal burning power plants in decades, it does not buy any energy

Very diverse, Natural gas #1, Renewables are growing FAST

Global coal deposits:

1. US (~25%)

2. Russia (15%)

3. Australia (14%)

4. China (13%)

5. India (10%)

Alternatives

• Hydropower is mostly maxed out 

  • No GHG

  • Extremely efficient

  • Very cheap

• Wind power is set to expand

  • Cheap, clean

  • Noisy, impacts to wildlife

• Solar power is set to expand

  • Low/No GHG production

  • Requires light (doesn’t work at night)

  • Costs are decreasing

  • By heating up salts to turn a wheel it stores energy over time as the sun sets (stores energy)

  • Photovoltaic cells are more efficient at lower temps

• geothermal expansion is also set to expand - but not as much

  • Uses hot water to turn a wheel

  • Little to no GHG

  • Highly reliable and sustainable

  • CA is a global leader in geothermal electricity generation

• Battery technology and the inflation reduction act could change the solar production

Global Economy

Nordhaus says that the world GDP % will go down with an increase in global mean temp. Stern agrees but to a slightly lesser degree

Boron

B concentrations are highly dependent on the pH of the ocean which is dependent on the concentration of CO2 in the atmosphere. More B11 (not B10) in the shells of organisms means highly acidity and more CO2.