Climate Change - Learn Plant Science

Weather Vs Climate

Weather	Climate
short term changes in the atmospheric variables in a given area over a short period of time (hours/days)	Average weather conditions of particular area long over period time (3 decades or more)

Example for the climate changes – Glacial and interglacial periods, earth is currently at the interglacial phase but this phase is relatively long than previous interglacial phase due to warming up since the last century, each cycle lasting approximately 100000 years

Glacial period (ice age) – ice sheets expand, cover a significant portion of the Earth’s surface, lower sea levels

Interglacial period – ice sheets retreat, sea levels rise, and the climate becomes more suitable for human civilization

Greenhouse effect

Natural greenhouse effect – Solar radiation is absorbed by the earth surface and radiate back to the atmosphere as infrared radiation. this infrared radiation interact with the greenhouse gases (CO₂,H₂O…)and increasing their kinetic energy, resulting warming of the lower atmosphere.

Intergovernmental Panel on Climate Change (IPCC) – The Fifth Assessment Report

More than 95% probability that human activities over the past 50 years have warmed the planet.
Over 95% probability that human-produced greenhouse gases such as carbon dioxide, methane and nitrous oxide caused much increasing in Earth’s temperatures over the past 50 years
Four long lived GHGs – CO2 , methane (CH4 ), nitrous oxide (N2O) and halocarbons (a group of gases containing fluorine, chlorine or bromine).
They affect the absorption, scattering and emission of radiation within the atmosphere and at the Earth’s surface. (AR4 SYR Synthesis Report – 2.2 Drivers of Climate Change, n.d.)

Human activities that impact on climate changes

Rice cultivation
Ruminant animals
Conversion of forest lands, biomass clearing
Burning agricultural residues
Fertilizer applications
Carbon emissions from organic soils (Peat) when these soil use for agricultural practices it will releases large amount of CO₂ to the environment

Rice cultivation

Rice is grown in flooded water, it creates a anaerobic environment, methanogenic bacteria in soil releases methane.
Forest clearness to paddy field cause to increasing the CO₂ levels.
Fertilizers used in rice cultivation releases the N₂O.

Ruminant animals (Cows, sheeps, goats)

Methane is produced by digestive process of the ruminant animals

Conversion of forest lands, biomass clearing

Deforestation and biomass cleaning contributed to climate changes due to by reducing the absorption capacity of CO₂ of the biosphere.

Evidence for negative climate changes

Increase in global temperature – Over the past century, the Earth’s average surface temperature has increased by about 1.1 ⁰C
Increase the average CO₂ level in the atmosphere.
Increasing the droughts and precipitation patterns
Lengthening the growing seasons
Melting glaciers
Increasing the sea level. – due to melting of ice and thermal expansion
Acidification of environment – due to increasing CO₂ level
Extreme weather conditions.

Associate problems due to increasing the sea level.

Destroy the coastal estuaries, wetlands, coral reefs
Fishing in coastal areas affected
Climate refugees – sea level rise leads to displacement of the populations.
Contamination of fresh water coastal aquifers – lowers the amount of freshwater available for drinking and irrigation

Negative impact on human due to the climate changes.

Food security – reducing the crop yield, increasing the susceptibility for pests and diseases due to changes in temperature and precipitation pattern. Changing the planting and harvesting times it difficult to predict the when to start framing and when to start planting. Increasing the prevalence of pest and diseases under warm temperature proliferate the pest growth. Damage fisheries and aquaculture due to temperature rise and increasing the CO₂ level in water.
Human health – Heat exposed,dehydration, increasing the prevalence of the vector borne diseases such as malaria, dengue, respiratory illness due to increasing of ground level ozone level rise and other pollutant gases.
Economic impacts – reduce the agricultural productivity, damage agricultural infrastructure, loss of coastal infrastructure, increased costs associated disaster such as floods, droughts, and wildfires, loss of natural resources

How to deal with climate changes

Mitigation – Actions that are taken to prevent or reduce the rate of the climate changes

Reducing the fossil fuel
Reducing the deforestation and promoting reforestation.
Implementing policies and regulation – in order to promoting the renewable resources,encourage emissions reduction (carbon taxes)

Adaptations – actions taken to cope with the impacts of climate change that are already happened or are expected to occur in the future

Developing early warning systems for disaster preparation such as flood
Increasing the infrastructure of the coastal area.
Development of climate resilience crops such as flood resistance and drought résistance crops.
Sustainable land use practices – conserve wetland and forest

Tipping points/elements of climate system .

Large scale components in the earth system, which are characterized by a threshold behavior. Small changes can leads to large irreversible impact. e.g. – melting of the greenland sheet can cause to sea level rise and it can not be reversed.

References

(2018, April 1). Cyclical pattern of glacial-interglacial conditions.jpg. Wikimedia. https://commons.wikimedia.org/wiki/File:Cyclical_pattern_of_glacial-interglacial_conditions.jpg
Coastal hydrogeology – Wikipedia. (2022, November 16). Coastal Hydrogeology – Wikipedia. https://en.wikipedia.org/wiki/Coastal_hydrogeology
Tipping points in the climate system – Wikipedia. (2022, July 17). Tipping Points in the Climate System – Wikipedia. https://en.wikipedia.org/wiki/Tipping_points_in_the_climate_system
AR4 SYR Synthesis Report – 2.2 Drivers of climate change. (n.d.). AR4 SYR Synthesis Report – 2.2 Drivers of Climate Change. https://archive.ipcc.ch/publications_and_data/ar4/syr/en/mains2-2.html