(Photo: Kathryn Mersmann/NASA’s Scientific Visualization Studio)
It’s very important to know the meaning and understand the concepts of many terms, abbreviations, and acronyms relevant to climate change topics to fully understand the debates, talks, and critics on climate change.
Some terms definition are easy to follow but the concepts behind it can be overwhelming to be fully understood. Here is a list of some of the most used terms on climate change topics with its simple definitions that you should learn.
Weather refers to atmospheric conditions in the short term. Changes in such as temperature, precipitation, humidity, wind, cloudiness, wind, visibility, and other meteorological conditions.
Climate is different from weather. Climate is the average weather patterns over a longer period.
The atmosphere refers to the gaseous envelope surrounding the Earth. The atmosphere consists of nitrogen (78.1%), oxygen (20.9%), water vapor (1%), argon (0.93%), helium, carbon dioxide (0.035%), ozone, clouds, aerosols, and other gases.
Biosphere refers to all ecosystems and living organisms in the atmosphere, land (terrestrial biosphere), or oceans (marine biosphere).
Ecosystem refers to any natural unit or entity including living organisms and non-living parts that interact to produce a balanced system through the cyclic exchange of materials.
Climate science is the study of how changing climates affect the natural order on a global level.
Climate change refers to the long-term pattern of changes in the Earth or a region on Earth’s climate. Climate change may be caused by natural processes and human activity. Changes in such as sea levels, sea ice, variations in the amount of snow.
Global warming is different from climate change. Global warming is an increase in the Earth’s average surface temperature caused by human-made greenhouse gas emissions. Increasing levels of greenhouse gases would increase global warming.
Anthropogenic describes a process or result generated by human beings. Usually used in the context of man-made emissions.
Anthropogenic climate change
Anthropogenic climate change refers to the climate change caused by human activities as opposed to natural processes.
Global average temperature
Global average temperature is a long-term look at Earth’s average air temperature on land and sea. Its recordings are from weather stations and satellite measurements. It’s usually over 30 years. 2006-2015 was the warmest decade on record since thermometer-based observations began nearly 150 years ago.
Carbon is a configuration of molecules and an elemental building block of all organisms on Earth.
Carbon footprint refers to the amount of carbon emitted by an individual or organization in a given period; or the amount of carbon emitted during the manufacture of a product.
The carbon cycle describes the process by which living things absorb carbon from the atmosphere, soil, sediments, or food.
Carbon sequestration is the process of storing carbon dioxide. It removes carbon dioxide from the atmosphere and storing it in a fixed molecule in soil, plants, or oceans. This can happen naturally by trees and plants. It can also refer to the capture and storage of CO2 by industry.
Carbon offsetting refers to the way of compensating for CO2 emissions by participating in or funding efforts to take CO2 out of the atmosphere. Offsetting works by paying another party to save emissions equivalent to those produced by your activity.
A greenhouse gas is a chemical compound found in the Earth’s atmosphere. Greenhouse gas traps heat in the atmosphere and then warms the Earth. The main greenhouse gases are water vapor (H2O), carbon dioxide, methane, nitrous oxide, hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6).
These gases in the atmosphere are increasing faster than they are removed. Increasing levels of greenhouse gases would increase global warming.
Carbon dioxide (CO2) is a gas in the Earth’s atmosphere. It’s the primary greenhouse gas and driver of climate change. It occurs naturally and is also from human activities such as burning fossil fuels. 82% of total US greenhouse gas emissions are from carbon dioxide.
Methane (CH4) is a chemical compound that’s the main component of natural gas. Methane is a greenhouse gas. The main contributors are agriculture, wood-burning from stoves and fireplaces, livestock digestive systems, leaks from coal mining, and decomposition in landfills. 10% of total US greenhouse gas emissions are from methane.
Nitrous oxide (N2O) is one of the main greenhouse gases. The main contributors are animal waste and nitrogen fertilization of the soil. 6% of total US greenhouse gas emissions are from nitrous oxide.
PPM (Parts per million)
PPM is a way of expressing the concentration of one component in the larger sample. It used to describe the concentration of pollutants in the atmosphere like carbon dioxide or methane. Carbon dioxide levels that considered safe are should be at 350 ppm. Now, we’re at about 408.53 ppm. And this number is growing by approximately 2 ppm each year.
Pre-industrial levels of carbon dioxide
Pre-industrial levels of carbon dioxide refer to the concentration of carbon dioxide in the atmosphere before the start of the Industrial Revolution. It estimated by scientists that pre-industrial levels of carbon dioxide were about 280 ppm. It’s well below where we are today.
Emissions refers to substances such as greenhouse gases which released into the air that are produced by numerous activities. Activities such as industrial agriculture, burning fossil fuels, melting permafrost, others. Emissions are measured by their concentrations in the atmosphere as PPM.
Biogenic emissions are emissions generated by living things
Fossil fuels are natural sources of non-renewable energy. Fossil fuels formed from the remains of living organisms that were buried millions of years ago. When burnt, it produced carbon dioxide. Fossil fuel sources such as coal, oil, and natural gas. In 2017, 93% of US sources of carbon dioxide emissions are from fossil fuels combustion.
Renewable energy is energy that sourced from naturally replenished resources. It means that they will renew themselves within our lifetime. Renewable energy sources include solar, water, wind, geothermal heat, and biomass.
Solar power refers to the energy harnessed from the sun. Solar power can be transformed into thermal and electric energy.
Biofuels refers to the renewable energy derived from biological materials. Biological materials such as plants, crops, wood, algae, tires, fish oils, agricultural waste, and other types of waste. Biofuels such as ethanol, methanol, biodiesel.
Deforestation refers to the permanent conversion or removal of forested lands for non-forest uses. Deforestation can lead to significant levels of carbon dioxide emissions for two reasons. First, the burning or decomposition of the wood releases carbon dioxide. Second, trees that once removed carbon dioxide from the atmosphere are no longer present.
Reforestation refers to the planting of forests on lands that have previously contained forests but have been converted to some other use.
Afforestation refers to the planting of new forests on lands that historically haven’t contained forests.
Habitat fragmentation refers to a process during which larger areas of habitat are broken into several smaller patches of smaller total area.
Sea-level rise refers to the increase in the average level between high tide and low tide where sea surface meets a shoreline. It’s caused by two major causes: ice loss and thermal expansion. Glaciers and land ice melt causing more water to be released into the ocean; and the ocean expands as its temperatures increase.
Ice loss refers to the retreat of sea ice and land ice mass from its historic extents. It’s one of two major causes of sea-level rise.
Thermal expansion refers to the increase in volume and decrease in density that results from warming water. Warming ocean leads to an expansion of the ocean volume, which leads to an increase in sea level.
Ocean acidification is the change in ocean chemistry due to decrease in pH levels or an increase in acidity, in seawater. The ocean absorbs approximately one-fourth of man-made CO2 from the atmosphere. Ocean acidification can kill off coral reefs and decrease marine organism’s ability to build their skeletal and shells structures.
Coral bleaching refers to the process in which a coral colony expels the microscopic algae (zooxanthellae) that live in symbiosis with their host organisms (polyps), under environmental stress. The affected coral colony will appear whitened.
Heatwaves refers to a prolonged period of excessive heat and often combined with excessive humidity.
The Least Developed Countries (LDCs) represent the weakest and poorest countries in the world as determined by the UN. The LDCs have low indicators of socioeconomic development, human resources, and economic vulnerability. The current LDCs list includes 49 countries which 33 are in Africa, 15 in Asia and the Pacific, and one in Latin America.
The United Nations Framework Convention on Climate Change (UNFCCC) is an environmental treaty that nations joined in 1992. The goal is to stabilize greenhouse gas concentrations in the Earth’s atmosphere at a level to prevent dangerous human interference with the climate system.
The Kyoto Protocol is a protocol attached to the UNFCCC, which sets legally binding commitments on greenhouse gas emissions.
COP (Conference of the Parties)
The COP to the UNFCCC is a yearly international climate conference. It’s where nations assess progress and determine steps for action through the UNFCCC treaty.
IPCC (Intergovernmental Panel on Climate Change)
The IPCC is a scientific body established by two UN organizations, the UN Environment Programme and the World Meteorological Organization that set up in 1988. They review and assess the research relevant to climate change happening all around the world and report to the public about the current state of our scientific knowledge. The IPCC was honored with the 2007 Nobel Peace Prize.
A tipping point is a threshold for change which when reached, results in a process that is difficult to reverse. Now, policymakers are urged to halve global greenhouse emissions over the next years. If not, it risks triggering irreversible changes in Earth’s climate system.
Climate change vulnerability
Climate change vulnerability refers to the degree to which a system is susceptible to and unable to cope with, adverse effects of climate change.
Climate resilience refers to the capacity for a socio-ecological system to absorb stresses and maintain function from significant multi-hazard threats from climate change with minimum damage to the economy, social well-being, and the environment.
Climate change mitigation
Climate change mitigation refers to an action that will reduce, prevent, or absorb greenhouse gas emissions. Climate change mitigation such as planting trees to absorb more CO2, using renewable energies, developing and deploying new tech, making older equipment more energy-efficient.
Climate change adaptation
Climate change adaptation (CCA) refers to the adjustments societies or ecosystems make to limit the negative effects of climate change or to take advantage of opportunities provided by a changing climate.
Climate change adaptation such as conversion to crops capable of surviving drought and high temperatures, and construction of barriers to protect against rising sea levels.
• BBC News. 2014. “Climate Change Glossary.” Science & Environment. April 13. →
• The Climate Reality Project. 2015. “Key Terms You Need To Know To Understand Climate Change.” October 27. →
• UC Davis. “Climate Change Terms and Definitions.” Science & Climate. →
• United States Environmental Protection Agency. 2017. “Glossary of Climate Change Terms.” Climate Change. January 19. →