YATAĞAN ŞEHİT ENGİN YALÇIN MTAL /AYŞE JULİDE AKZEYBEK Avatar works

 

YATAĞAN ŞEHİT ENGİN YALÇIN MTAL / Ayşe Julide Akzeybek / Poster works

 

YATAĞAN ŞEHİT ENGİN YALÇIN MTAL / Ayşe Julide Akzeybek Logo works

 

Greenhouse gases

Climate change has a precise definition: systematic change in the long-term state of the atmosphere over multiple decades or longer. In the scientific literature, climate change may refer to a combination of human-induced and natural climatic changes or only human-induced changes. There is at least a 99 percent chance that average global temperatures have significantly increased from 1950 to present.

The most important greenhouse gas is CO. CO is naturally emitted to and absorbed from the atmosphere through plant photosynthesis and animal respiration and volcanic eruptions. Although the cycle of CO is a natural process, humans have been discharging increasing amounts of CO, through the burning of fossil fuels (oil, coal, and natural gas) for energy and transportation, solid waste, trees, and wood products. We have also been increasing atmospheric CO, through land use changes such as deforestation. Human activities such as fossil fuel use and land use change have emitted so much CO, into the atmosphere that natural CO, sinks (sources of CO absorption such as oceans and plants) and cannot absorb the excess CO. Indeed, since the eighteenth century, atmospheric CO, concentrations have increased by 40 percent from approximately 280 parts per million by volume (ppm) to 398 ppmv in 2014. The current CO, level has not occurred for over 850,000 years (National Research Council 2010) and is not a result of natural CO, variation in the atmosphere.

Methane (CH), an important GHG, is emitted into the atmosphere through several processes. CH is naturally emitted from wetlands and other natural areas through the decomposition of organic materials, and it is naturally removed from the atmosphere through soil and chemical reactions. Humans emit CH through the production and use of fossil fuels and commercial livestock where it is produced from the creation and decomposition of manure in holding tanks and lagoons. The processing and decomposition of human solid waste in landfills and treatment facilities also produce CH.