Climate change has been going on for billions of years, even as we blame anthropogenic causes for the impacts that are already happening, is not a function of anthropogenic causes alone, the earth has gone through warming and cooling phases in the past, long before human beings inhabited the earth.
Climate is the average pattern of weather elements; precipitation, temperature, humidity, sunshine, wind velocity, and phenomena such as fog, frost, and hailstorms, taken over a 30-year period for a particular region.
We are at a time when the climate has changed. This change has occurred in the elements of weather including precipitation, temperature, humidity, sunshine, wind velocity, and phenomena such as fog, frost, and hailstorms that have caused a change in the weather patterns.
Climate Change refers to a change in the state of the climate that persists for an extended period, typically decades or longer.
Climate change may be due to natural and anthropogenic processes meaning it is caused by both natural phenomena as well as human activities that alter the chemical composition of the atmosphere through the build-up of greenhouse gases which trap heat and reflect it back to the earth’s surface, resulting in global warming.
Forces that can contribute to climate change include the sun’s intensity and the earth’s orbit around the sun, called Milankovitch cycles, these cycles have occurred at different intensities on multi-millennial time scales of between 10,000 years and 100,000 years periods, volcanic eruptions are also known to cause a change in the chemical composition of the atmosphere, and this is compounded by changes occurring due to greenhouse concentrations in the atmosphere driven by human activity.
The impacts of global warming intensified during the 19th century due to rapid population growth, and the extension, and intensification of agriculture so as to feed the growing population and cloth it as well through the growing of food as well as cotton for textiles respectively. During this period, the growth in natural environmental changes caused by humans is clear, as it is marked by significant changes in sedimentation in the lakes and rivers as land is tilled for farming to grow crops while encouraging soil erosion due to the loosening of the soil. Activities such as population growth, urbanization, building and construction, an increase in vehicular stock, and commodity production are all contributors to greenhouse gas emissions that have increased the concentration of greenhouse gasses in the atmosphere.
Some of the natural causes of climate change are climate variations, and variabilities that are periodic like the El Nino Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD) whose occurrences in cycles have been changing from seven years, to five and now to just two years and how these interact with the climate system, there are also the volcanic eruptions that are natural and contribute to changes in climate. Studies of Paleoclimate have shown how the earth has been reconstructing and how Earth’s climate reacted to natural “pushes”, such as changes in the planet’s orbit. Another example is the Earth’s wobble which is a natural occurrence. Other natural external factors are changes in the solar input depending on the earth’s movement on its axis around the Sun.
The industrial revolution and dieselization, the use of diesel which is a fossil fuel as well as coal as a source of energy in various production processes have contributed to the anthropogenic changes in the climate system by increasing the greenhouse gas concentration in the atmosphere.
The first industrial revolution of 1760 to 1840 saw the development of mechanization and steam power, this led to the second industrial revolution of 1870 to 1914 when mass production was realized through the use of electricity produced from fossil fuels like diesel. The latest industrial revolution was from 1950 to 2000 the era of automation computerization. Of all these, the industrial revolution that began in 1760 saw production processes move from an agrarian and handicraft economy to domination by industry and machines for production, this was to satisfy the rising demand for goods and food, due to the sharp rise in population. The invention of the automobile in 1900 by Henry Ford served to introduce unbridled consumption.
Since the 1950s, many of the observed changes in greenhouse gas concentration have been unprecedented. The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, and sea levels are rising all this is because of global warming due to the high concentrations of greenhouse gases in the atmosphere.
Greenhouse gases are those gaseous constituents of the atmosphere, both natural and anthropogenic, that absorb and emit radiation at specific wavelengths within the spectrum of infrared radiation emitted by the Earth’s surface, the atmosphere, and clouds, this results in the greenhouse effect.
Greenhouse gases include; Water vapour, carbon dioxide, nitrous oxide, methane, and ozone these have been compounded by human-made greenhouse gases like sulphur hexafluoride, hydrofluorocarbons, and perfluorocarbons.
COP21 was supposed to be the turning point, the signing of the Paris Agreement whose aim was to strengthen the global response to the threat of climate change, in the context of sustainable development and caped the rise in global temperatures to below 2°C above pre-industrial levels was the main rider to the global response to mitigating the impacts arising from global warming.
Among the main aims of the Paris Agreement was to pursue efforts to limit the temperature increase to 1.5°C above pre-industrial levels, recognizing that this would significantly reduce the risks and impacts of climate change;
Increasing the ability to adapt to the adverse impacts of climate change and foster climate resilience and low greenhouse gas emissions development, in a manner that does not threaten food production; and
Making finance flows consistent with a pathway towards low greenhouse gas emissions and climate-resilient development.
Protecting natural carbon sinks like forests and oceans, creating new sinks through silviculture (the care and cultivation of forest trees), or green agriculture are also elements of mitigation that can be pursued under the Paris Agreement.
Judith Akolo is a Development Journalist with the Kenya Broadcasting Corporation and is also a Masters of Climate Change and Adaptation student at the University of Nairobi.
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