Understanding Climate Change and Its Impact on the Environment

Posted on Nov 29, 2023 in Geology

Climate Change and Its Impact

Climate change occurs when the patterns change in time (winter months get warmer) and space.
Why be interested in cc?

  • Determines human-managed ecosystems.
  • Effects on the weathering of rock, the type of soil that forms, and the rate of soil formation.
  • Determine the quantity and quality of water available for human use.
  • Determines the severity of droughts, storms, and floods.
  • Determines the nature and locations of biomes.

How do we study cc?

  • Air bubbles in ice cores
  • Annual tree rings
  • CO2 measured continuously at Mauna Loa Observatory

Times of glaciation occur episodically on Earth because of systematic changes in the distance and orientation of Earth relative to the Sun.

Greenhouse Effect

  1. sunlight reaches the earth
  2. some energy is reflected back into space
  3. some is absorbed and re-radiated as heat
  4. most of the heat is absorbed by GHG, and reflected in all directions, warming the earth.

GHG: gas that absorbs infrared radiation. Ex: Carbon dioxide, methane, nitrous oxide, Water vapor: the most abundant GHG
other GHGs: Methane and nitrous oxide
Human activities like agriculture, deforestation, and fossil fuel use release CO2 and other GHG.
Natural factor that influence cc:

  • Variations in the Sun’s output of energy.
  • Dust and gasses from volcanic eruptions.

Infrared Radiation: radiation that has a wavelength

Causes of Climate Change

  • Greenhouse gas and CO2 concentrations increasing
  • Burning fossil fuels
  • Deforestation.

50% of human caused CO2 stays in the atmosphere, while the other 50% is absorbed by the ocean.
The atmosphere: a collection of gasses held by gravity around the Earth.
Lowest to highest levels

Troposphere:

  • Gasses moderate the flow of energy to Earth.
  • Ranges from 5 to 10 miles thick.
  • Contains almost all the water vapor and clouds.
  • Gets colder with altitude.
  • Mixed air allows pollutants to reach the top of the layer.

Tropopause:

  • Air shifts from cooling with height and begins to warm.

Stratosphere:

  • temperature increases with altitude.
  • Ozone (O3) absorbs the Sun’s high-energy radiation.
  • Due to little mixing and no precipitation, substances remain for long periods of time.

Mesosphere and thermosphere:

  • declining ozone levels.
  • Only small amounts of oxygen and nitrogen.

The atmosphere-ocean-land system is a huge weather engine.
Driven by the Sun and affected by Earth’s rotation and tilt.
Solar energy is reflected or absorbed by Earth.
Absorbed energy heats the ocean, land, and atmosphere.
Evaporation, convection, and reradiation of infrared energy release energy.
Fourth Assessment Report (AR4): first report from IPCC that stated that CC was a reality and caused by human activity
IPCC: Provides accurate and relevant information leading to understanding human-induced climate change
  Working Group I: assesses scientific issues of climate change.
 Working Group II: evaluates impacts and adaptation to it.
 Working Group III: investigates ways to mitigate its effects.

  • Evaporation: supplies water vapor to the atmosphere
  • Condensation: supplies heat to the atmosphere
  • Heat capacity: oceans absorb energy with heated water

Ocean-atmosphere oscillations: These processes produce globally erratic climates

  • NAO: atmospheric pressure centers switch back and forth across the Atlantic (Switching wind and storms)
  • ENSO: shifts atmospheric pressure over central equatorial Pacific Ocean

Warming and Cooling processes

  • Earth absorbs and converts energy to heat
  • Infrared heat energy radiates back to space

Cooling processes

  • Planetary albedo: sunlight reflected by clouds prevents warming
  • Snow and ice contribute to albedo by reflecting sunlight

Aerosols cangel some GHG gasses
Ocean warming
Over the last decade, oceans have absorbed most of the non-atmospheric heat
A long-term consequence: the impact of this stored heat.
A short-term consequence: rising sea levels
Melting decreases ice, which decreases albedo leading to further warming.
Photosynthesis
A process in which solar energy is transformed into chemical energy, takes place in the chloroplast of plants.
Thylakoids contain the pigments that capture solar energy. 6 CO2 + 6 H2O + light energy C6H12O6 + 6 O2
uses carbon dioxide and water releases oxygen and glucose

Mitigation

  • take action to prevent emissions
  • Every country will be affected, but especially the poorest
  • We must reduce emissions of GHGs

Adaptation

  • anticipate harm and plan adaptive responses to decrease vulnerability of people, property, and the biosphere.

Examples of adaptation strategies:

  • Agriculture: climate-resistant crops, irrigation
  • Structures: seawalls, reservoirs, revegetation of coasts
  • Emergency preparedness: early-warning systems
  • Reducing risks: financial safety nets, proper insurance
  • Development, controlling diseases, economic progress

Achieving stabilization: The Framework Convention on Climate Change (FCCC) Kyoto Protocol: the third Conference of Parties to the FCCC met in 1997 in Japan to craft a binding agreement on reducing emissions Weaknesses of the protocol:
  
 • The protocol’s targeted reduction will not stabilize ghgs 

  • The world’s largest GHG emitters are not participating
  • India, China, the U.S. New funds:

Least Developed Countries Fund: advises countries on national adaptation strategies
Special Climate Change Fund: provides financial assistance to countries affected by climate change
Adaptation Fund México and climate change
1980 World Conservation Strategy:

  • Preserve fundamental ecological processes
  • Preserve genetic diversity
  • Allow the sustainable use of species and ecosystems

PROFEPA, Conabio, SEMARNAT (instituciones que lidian con CC)
SEMARNAT:

  • stop: actions that provoke the degradation of the environment
  • reverse: rates of environmental degradation
  • restore: all damaged ecosystems
  • adopt: ample treatment in environmental topics