Global Climate Change and Its Impact
Image by Gerhard G. from Pixabay
Climate change is the most significant challenge facing humanity in the 21st century. It jeopardizes economic growth, human well-being, ecological safety, and available resources. Human activity, mainly burning fossil fuels, is the leading cause of current climate change due to the emission of greenhouse gases. These GHGs accumulate in the Earth‘s atmosphere, which leads to less heat escape into space and thereby an increase in temperature (IPCC).
Since the 19th century, global warming has been aggravated due to the increase in GHG emissions levels, particularly CO2 emissions. Since the industrial revolution began, the concentration of CO2 in the atmosphere has increased from 280 parts per million (ppm) to 417 ppm in July 2021. Astonishingly, the rise of emissions has snowballed since the 1950s. As a result, the increased level of emissions led to an increase in global temperature. As a result, the global mean surface temperature increased by 0.74 ±0.18°C in the 20th century and is likely to increase by between 1.4 and 5.8°C by the end of the 21st century from 1990 (IPCC, 2001b). However, the IPCC (2007) has set a CO2 concentration target of 450 ppm to limit the global average temperature rise to 2oC. They also demonstrated that the global average temperature increase could be defined between 2 and 2.4oC (350-400 ppm CO2) only through 50% to 85% CO2 emissions reduction by 2050 relative to the 2000 level.
What Is Climate Change?
Climate is the average weather in a place over many years. Climate change refers to a long-term shift in those average conditions. These shifts may be a natural process where temperature, rainfall, wind, and other elements vary over decades or more. Our planet Earth is now in a period of rapid climate change, with global temperatures rising because of human activities, such as burning coal, oil, and gas.
When we burn fossil fuels, it generates greenhouse gas (GHG) emissions. The GHG act like a blanket wrapping the Earth, thereby trapping the solar heat and increasing temperatures. Some examples of GHG emissions that cause climate change include CO2, which is released from using fossil fuels for driving vehicles, or coal for electricity. The clearing of land and deforestation also release CO2. In addition, garbage sent to landfills is a significant cause of the emission of methane gas. The leading emitters of GHG are buildings, industry, transport, energy, land use, and agriculture.
What is the impact?
People
Climate change affects our health, our ability to grow food, causes water shortages, and impacts housing, safety, and work.
Extreme weather events - heatwaves, downpours, and storms - will become more frequent and intense, threatening lives and livelihoods.
Many of us are already vulnerable to climate impacts, such as those who live in small island nations and developing countries.
Certain conditions such as rise in sea level and intrusion of saltwater have advanced to the stage that the whole communities had to relocate, and prolonged droughts are leading to the risk of famine. We face the danger of an increase in the number of “ climate refugees” in the future.
Environment
We have seen that the polar ice and glaciers are melting rapidly, thereby contributing to the rising sea levels.
As permafrost - the frozen ground melts in Siberia and other cold regions of the earth, methane gas will be released into the atmosphere, thereby deteriorating climate change.
The weather conditions needed for wildfires are becoming more likely, and low-lying coastal areas are threatened with flooding by rising seas.
Nature
As their habitats change, some species will be able to move to new locations. But climate change is happening so rapidly many are likely to become extinct. Polar bears are at risk of disappearing as the ice they rely on melts away. As oceans absorb more CO2 and become more acidic. Tropical coral reefs may disappear
Global Initiatives
At a global level, world leaders have responded to the climate change challenge through several international agreements. For example, the United Nations Framework Convention on Climate Change (UNFCCC) was established in 1992 intending to achieve the ―stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system within a time frame sufficient to allow ecosystems to adapt naturally to climate change, to ensure that food production is not threatened and to enable economic development to proceed sustainably.
After the five years of the UNFCCC establishment, the Kyoto Protocol was created in 1997 to reduce GHG emissions (UN, 1998). The first commitment period started from 2008-2012, in which industrialized countries (known as ‗Annex 1‘nations) committed targets to reduce GHG emissions by 5% below 1990 levels. The new target to reduce GHG emissions by 18% below 1990 levels was achieved under the second commitment period (2013-2020).
Later in the 21st century, global efforts have been accelerated to reduce GHG emissions and limit global average temperature. First, the 2010 Cancun Agreement (UN, 2010), in which countries have agreed to limit global temperature by two °C compared to pre-industrial levels by determining the CO2 concentration in the range of 450ppm-490ppm, of which requires a reduction in global emissions in the field of 50-85% by 2050 compared to 2000 levels.
Second, the G7 Summit, in 2015, in which the G7 leaders committed to decarbonizing the global economy by the end of the century; reduce 40 to 70% of worldwide emission and energy sectors transformation of G7 nations by 2050 (G7 Summit, 2015).
Third, Sustainable Development Goals (SDGs) (UN, 2015), in which 2030 plan was created for 17 SDGs including SDG 7 and SDG 13 for sustainable energy and climate change respectively: and
Fourth, the Paris Agreement (UNFCCC, 2015) in 2015, to strengthen the 2010 Cancun Agreement commitment to well below 2°C. The new agreement in which about 200 nations committed in the form of ―Intended Nationally Determined Contributions (INDCs) targets to reduce their GHG emissions in 2030. At the end of July 2018, 179 countries ratified the Paris Agreement; as a result, INDCs change into ―Nationally Determined Contributions‖ (NDCs).
In October 2018, IPCC published the ―special report on global warming of 1.5 °C in which shows the urgency to limit global warming to 1.5 °C by reducing emissions to zero by 2050.
What can we do about it?
Both organizations and individuals can reduce their carbon footprint which can help in reversing the damage done to the environment. We have posted two articles on carbon footprinting - one for organization action points, and the other for the individual. You can read them here.
Organizational Carbon Footprinting
The Climate Change 2021 - IPCC Report
The increase in the average surface temperature of the Earth will cross 1.5 degrees Celsius in the next 20 years and two °C by the middle of the century without a sharp reduction in emissions
With every one °C rise in temperature, there will be a 7% increase in the intensification of extreme rain events.
Carbon dioxide (CO2) concentrations are the maximum in at least 2 million years
Sea level rise is the fastest in 3,000 years and will continue for hundreds of years.
Arctic sea is lowest in 1,000 years
Ice melting will continue for the next 1,000 years even if we manage to control our GHG emissions.
Ocean warming has increased by 2-8 times from the 1970s and will continue.
The Way Forward
Many of the climate change solutions can deliver economic benefits as well while improving our lives as well as protecting our environment. We also have international agreements to guide the progress, such as the UN Framework Convention on Climate Change and the Paris Agreement. The three broad action categories are: reducing emissions, adapting to climate impacts, and financing the adjustments.
Switching the energy systems from fossil fuels to renewable energy like solar or wind can reduce the emissions driving this climate change. But we have to accelerate the pace of this adaption. While a growing alliance of countries is pledging to net zero emissions by 2050, about a half of the emission cuts must be achieved by 2030 to keep the global warming below 1.5°C. Global fossil fuel production should decline by around 6 percent per year from 2020 to 2030.
Adapting to the consequences of climate change protects people, habitats, infrastructure, businesses, livelihoods, and ecosystems. It covers the current impacts and those that are likely in the future. While this adaptation will be required everywhere, it must be prioritized for the most vulnerable people with the least resources available to cope with the climate hazards. The rate of return can be highly rewarding. For instance, the early warning systems for disasters save lives and property and thus can provide paybacks up to 10 times the original cost.
Written by Inderjit Ahuja.