Climate Change Awareness

What is Climate Change ?

Climate change refers to long-term shifts in temperatures and weather patterns. Such shifts can be natural, due to changes in the sun’s activity or large volcanic eruptions. But since the 1800s, human activities have been the main driver of climate change, primarily due to the burning of fossil fuels like coal, oil and gas.

Burning fossil fuels generates greenhouse gas emissions that act like a blanket wrapped around the Earth, trapping the sun’s heat and raising temperatures.

The main greenhouse gases that are causing climate change include carbon dioxide and methane. These come from using gasoline for driving a car or coal for heating a building, for example. Clearing land and cutting down forests can also release carbon dioxide. Agriculture, oil and gas operations are major sources of methane emissions. Energy, industry, transport, buildings, agriculture and land use are among the main sectors causing greenhouse gases.

Source: https://www.un.org/en/climatechange/what-is-climate-change

What is Global Warming ?

Latest Annual Average Temp. Anomaly: 2023

1.28ºC | 2.3ºF

Source: https://climate.nasa.gov/vital-signs/global-temperature/

Global Land-Ocean Temperature Index

1.28ºC

This graph shows the change in global surface temperature compared to the long-term average from 1951 to 1980. Earth’s average surface temperature in 2023 was the warmest on record since recordkeeping began in 1880 (source: NASA/GISS)

The Greenhouse Effect

Source: https://science.nasa.gov/climate-change/causes/

“Climate change” and “global warming” are often used interchangeably but have distinct meanings.

Global warming is the long-term heating of Earth’s surface observed since the pre-industrial period (between 1850 and 1900) due to human activities, primarily fossil fuel burning, which increases heat-trapping greenhouse gas levels in Earth’s atmosphere. This term is not interchangeable with the term "climate change."

Since the pre-industrial period, human activities are estimated to have increased Earth’s global average temperature by about 1 degree Celsius (1.8 degrees Fahrenheit), a number that is currently increasing by more than 0.2 degrees Celsius (0.36 degrees Fahrenheit) per decade. The current warming trend is unequivocally the result of human activity since the 1950s and is proceeding at an unprecedented rate over millennia.

Year 2022 Global Surface Temperature change

This image shows the change in global surface temperatures. Dark blue shows areas cooler than average. Dark red shows areas warmer than average. Short-term variations are smoothed out using a 5-year running average to make trends more visible in this map. (source: NASA/GISS)

The Causes of Climate Change

Anthropogenic Causes

Four Major Gases that Contribute to the Greenhouse Effect

They contribute approximately with 96% of all Well Mixed Greenhouse Gases (a)

(a) According to RF (Radiative Forcing) - IPCC 2018 WG1AR5 Chapter 8

Carbon Dioxide

(CO2)

64.31%

A vital component of the atmosphere, carbon dioxide (CO2) is released through natural processes (like volcanic eruptions) and through human activities, such as burning fossil fuels and deforestation.

Methane

(CH4)

16.96%

Like many atmospheric gases, methane comes from both natural and human-caused sources. Methane comes from plant-matter breakdown in wetlands and is also released from landfills and rice farming. Livestock animals emit methane from their digestion and manure. Leaks from fossil fuel production and transportation are another major source of methane, and natural gas is 70% to 90% methane.

Nitrous Oxide

(N2O)

6.01%

A potent greenhouse gas produced by farming practices, nitrous oxide is released during commercial and organic fertilizer production and use. Nitrous oxide also comes from burning fossil fuels and burning vegetation and has increased by 18% in the last 100 years.

Chlorofluorocarbons

(CFCs)

9.06%

These chemical compounds do not exist in nature – they are entirely of industrial origin. They were used as refrigerants, solvents (a substance that dissolves others), and spray can propellants.

Increased Greenhouse Gas Concentrations are an Anthropogenic Factor

Evidence shows that current Global Warming is not correlated to Solar Irradiance

Several lines of evidence show that current global warming is not correlated by changes in energy from the Sun:

Since 1750, the average amount of energy from the Sun either remained constant or decreased slightly3.
If a more active Sun caused the warming, scientists would expect warmer temperatures in all layers of the atmosphere. Instead, they have observed a cooling in the upper atmosphere and a warming at the surface and lower parts of the atmosphere. That's because greenhouse gases are slowing heat loss from the lower atmosphere.
Climate models that include solar irradiance changes can’t reproduce the observed temperature trend over the past century or more without including a rise in greenhouse gases.