Environmental Factors: Climate Change

What facts support anthropogenic – human-caused – climate change?

  1. Increase in carbon dioxide (CO2) concentration in the atmosphere since circa 1850 from 280 ppm (pars per million) to 380 ppm by
    • Combustion of fossil fuels (coal, oil, gas, gasoline).
    • Deforestation

    The current CO2 concentration in the atmosphere is currently 0.04%.

  2. CO2 is a climate-altering gas that changes the Earth’s radiation budget (if the CO2 concentration of the air doubles, then the global mean temperature increases by about 3 °C).
  3. Since 1900, the global temperature has increased by circa 0.8 °C. The mean monthly temperatures of the last 10 years were globally the warmest since the beginning of temperature measurements in the 19th century.
  4. Most of the warming is due to increased carbon dioxide concentrations and other anthropogenic gases.Anthropogenic gases are those gases that come from human activity. They include, for example, carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), CFCs, etc. These gases cause the anthropogenic greenhouse effect (Engl. greenhouse effect)!!!

What factors speak for a natural climate change?

  1. The greenhouse effect is essential for human life. Without the greenhouse effect, the protective layer that reduces short-wave solar radiation (UV radiation) and partially retains long-wave radiation (infrared thermal radiation) from the Earth’s surface, which would otherwise escape into space, would be absent.
  2. Without natural greenhouse effect, the lower atmosphere would have a global average of only -18 °C.
  3. In the primordial Earth, we had 0.09% carbon dioxide and a global temperature on the Earth’s surface between 45-85 °C; this temperature is not explained by the greenhouse effect alone, but by a smaller continental area and more “transparent” atmosphere.
  4. Aside: humanity contributes only 3% to the current 0.04% C02 concentration.
  5. Climate is subject to natural variations: The climate records with the beginning of the 19th century is less than a blink in the entire history of the Earth’s climate. Note: The Little Ice Age was a period of relatively cool climate from the beginning of the 15th century until the 19th century. Before that, it was very warm: the warmest period was between 950 and 1250.These climate changes occurred without additional anthropogenic impacts!
  6. For the constant change in mean temperatures in the past (see below 4.) can not find any other cause (man-made CO2 is excluded!) Than the influence of the sun and clouds on climate events (see below 3.).