2.Impact_en_1
1.1
The Earth’s Climate System
The climate system is a complex system. Climate change and variation is due to the interaction exchange of matter and energy
The Earth’s Climate System
The Earth’s Climate System
Climate system, Earth's energy budget and Climate change
Earth’s energy budget accounts for the balance between the energy that Earth receives from the Sun, and the energy the Earth radiates back into outer space after having been distributed throughout the five components of Earth’s climate system. When the total of incoming energy is greater than the outgoing energy, Earth’s energy budget is positive and the climate system is warming. If more energy goes out, the energy budget is negative and Earth experiences cooling. Thus any changes to the Earth’s climate system that affect how much energy enters or leaves the system alters Earth’s radiative equilibrium and can force temperatures to rise or fall. The natural climate forces related to climate system are included;
The “Milankovitch Cycle” is a cyclical movement related to the Earth’s orbit around the sun. It is an important astronomical factor that causes changes to the Earth’s axis of rotation, the swing of the Earth’s axis and the orbit of the Earth around the sun. This causes the Earth to be close to or away from the sun, strongly influenced climatic patterns on Earth either during the higher or lower than normal global temperatures. This phenomenon occurs in cycles every 10,000 – 20,000 years. (Atsamon Limsakul, Kansri Boonpragob and Amnat Chidthaisong, 2011: 5) (Figure 5-2).
The “Albedo” is the portion of energy from the Sun that is reflected by the earth’s surface, the Earth’s surface is covered by many landcover types and related to diffused reflection of solar radiation back into the atmosphere such as clouds and ice sheets which are white, thereby Hight Albedo is capable of reflecting the sun rays back into the atmosphere well, the ground and forests are dark, thereby Low Albedo has the ability to absorb radiation from the sun. Consequently, the proportion of the material covering each area is an important mechanism for controlling the reflection of the sun’s rays and temperature of the Earth (Figure 5-3). It is also linked to solar radiation absorption and reflection into the atmosphere, which is incoming radiation is short-wave radiation when it hits the earth then transforms into heat energy or long wave radiation. If it can’t be reflected back into the atmosphere, it will cause accumulation of heat energy around the earth’s surface resulting in global temperatures rising, including other changes in the climate system (Figure 5-4).
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The Earth’s Climate System and Climate Change
Weather and Climate
“Weather” and “Climate” have different meanings as follows:
Weather phenomena refers to the atmospheric conditions that occur in a short period of time, such as weather for 3 hours, 1 day, 2 weeks, or occurrences of no more than 1 month. Meteorological measurements include temperature, humidity, air pressure, clouds, wind and rain. In contrast, Climate, sometimes understood as the “average weather,” is defined as the measurement of the mean and variability of relevant quantities of certain variables (such as temperature, precipitation or wind) over a period of time, ranging from months to thousands or millions of years, ranging from months to thousands or millions of years. The classical period is 30 years, as defined by the World Meteorological Organization (WMO). Climate in a wider sense is the state, including a statistical description, of the climate system. The weather and climate that occurs at local, regional and global scales are closely linkKansri Boonprakob, 2010. Basic knowledge about climate change models in Thailand climate change information volume 2: climate model and future climate. The Thailand Research Fund. [Amnat Chidthaisong (Author)] – WMO, FAQs – Climate,
Climate Change
Definition of Climate Change
Causes of climate change
IPCC, 2007: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K. B. Averyt, M. Tignor and H. L. Miller (deds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. .
Greenhouse Gases and Sources
Greenhouse gases are gases in the atmosphere that can absorb some of the Earth’s outgoing heat radiation and reradiate it back towards the surface, thus contributing to the “greenhouse effect”, Greenhouse gases have a profound effect on the energy budget of the Earth system which, if balanced, will maintain the surface temperature from a sudden change resulting in a warm and suitable temperature for the existence of life.
During the 18th Session of the Meeting of the Parties to the Kyoto Protocol 2012 in Doha, the Parties classified anthropogenic greenhouse gas emissions into 7 types, including:
- Carbon dioxide(CO2)
- Methane (CH4)
- Nitrous oxide (N20)
- Hydrofluorocarbons (HFCs)
- Perfluorocarbons (PFC)
- Sulphur hexafluoride (SF6)
- Nitrogen trifluoride (NF3)
Each greenhouse gas has its origin as follows:
- Carbon dioxide (CO2) generally has a natural source from volcanic activity and degradation of organic matter. But nowadays, human activities are the main factors in creating and releasing carbon dioxide such as fuels and fossils combustion etc.
- Methane (CH4) is a gas produced by decomposing waste in nature, but 60% of methane in the atmosphere is caused by human activities such as landfill waste disposal, burning wood fuel and agriculture etc.
- Nitrous oxide (N2O) is naturally sourced from bacteria, both soil and oceanic bacteria including the degradation of organic matter and sources of human activities such as industry production process, energy generation and consumption, agriculture and livestock, the burning of agricultural waste and various fuels.
- Hydrofluorocarbons (HFCs) are frequently used in air conditioning and refrigerants.
- Perfluorocarbons (PFCs) are another type of refrigerant.
- Sulphur hexafluoride (SF6) is a gas contained in an electrical control in transmittances system and electrical distributing devices for use as an electrical insulator preventing sparks from high voltage electrical equipment or helps to ventilate heat from high voltage electrical equipment.
- Nitrogen trifluoride (NF3) is a gas used in the production of electronic devices or circuits for computers.
| No. | Gas name | Lifetime (years) | GWP relative to CO2 for given time horizons | |
|---|---|---|---|---|
| 20-year | 100-year | |||
| 1 | Carbon dioxide(CO2) | * | 1 | 1 |
| 2 | Methane (CH4) | 12.4 | 84 | 28 |
| 3 | Nitrous oxide (N20) | 121 | 264 | 265 |
| 4 | Hydrofluorocarbons (HFCs) | 2 วัน – 800 | < 1 – 15,000 | < 1 – 12,400 |
| 5 | Perfluorocarbons (PFC) | 1.1 วัน – 50,000 | < 1 – 8,210 | < 1 – 11,100 |
| 6 | Sulphur hexafluoride(SF6) | 3,200 | 17,500 | 23,500 |
| 7 | Nitrogen trifluoride(NF3) | 500 | 12,800 | 16,100 |
Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Chang
Greenhouse gases concentration in the atmosphere
According to the IPCC-WG’s AR5, during the period from Industrial Revolution to present (1890 – 2014), there were increasing concentrations of greenhouse gases in the atmosphere caused by human activities with long-term predictions that the concentration of carbon dioxide in the atmosphere in the year 2100 will increase to 550-800 part per million (ppm) as shown in Figure 5-7. However, the concentration of carbon dioxide in the atmosphere will vary according to industries and world economy. The highest monthly average carbon dioxide concentration measurement at the Mauna Loa Station, Hawaii, The United States is 414.7 ppm (data as of May 2019), which is the highest detected in 61 years and which conform to long-term forecasts.
- IPCC, 2013: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernment Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 1535 pp.
- National Oceanic and Atmospheric Administration (2019). Carbon dioxide levels hit record peak in May. Retrieved December 9, 2019, from https://research.noaa.gov/article/ArtMID/587/ArticleID/2461/Carbon-dioxide-levels-hit-record-peak-in-May