Climate change

• Eccentricity


  The measure of a shape's deviation from being a circle, affecting the Earth's orbit and climate
• During the last ice age, the British Isles had many glaciers like the one in present-day Iceland
• Greenhouse gases

  • Carbon dioxide (CO2), methane (CH4), water vapor
• Global climate change has typically occurred very slowly over thousands or millions of years, but current climate change is happening more rapidly
• Changes in the Earth’s orbit, axial tilt, and precession

  Collectively known as 'Milankovitch cycles', these changes affect the amount of solar heat reaching Earth's surface, influencing climatic patterns and periods of glaciation
• Precession


  The Earth's wobbling on its axis, caused by gravitational pull, impacting seasonal contrasts between hemispheres and the timing of seasons
• Geological records show that there have been a number of large variations in the Earth’s climate caused by natural factors such as changes in the sun, emissions from volcanoes, variations in Earth’s orbit, and levels of carbon dioxide (CO2)
• Obliquity

  The tilt in the axis of the Earth, changing over time and impacting the warmth of summers and coldness of winters
• Strength of the Sun

  • Almost all of the energy affecting Earth's climate originates from the Sun, with its energy passing through space, being reflected back, or absorbed by the atmosphere. The Sun's energy output varies over time, impacting climate
• Water vapor is the most abundant greenhouse gas in the atmosphere but stays for a short period, while CH4 stays for about nine years until it is oxidized into CO2 and water
• CH4 stays in the atmosphere for about nine years until it is removed by oxidation into CO2 and water
• Ocean currents and carbon dioxide content

  1. Ocean currents carry heat around the Earth

  2. As oceans absorb more heat from the atmosphere, sea surface temperature increases and ocean circulation patterns change

  3. Increases in sea surface temperature can increase the amount of atmospheric water vapour over the oceans

  4. Warmer oceans can't absorb as much carbon dioxide from the atmosphere
• Meteorite impacts have contributed to climate change in the geological past
• Volcanoes and mountains formed by plate tectonics can influence the climate
• These gases trap solar radiation in the Earth’s atmosphere

  Making the climate warmer
• Water vapour stays in the atmosphere for just a few days
• Plate tectonic processes cause continents to move to different positions on Earth over very long periods of time
• Changes in land cover can affect global warming
• Volcanoes affect the climate through gases and particles thrown into the atmosphere during eruptions
• The world’s oceans absorb about a quarter of the CO2 released into the atmosphere every year
• CO2 stays in the atmosphere from years to centuries, contributing to longer periods of warming
• Water vapour is the most abundant greenhouse gas in the atmosphere
• Effects of large impacts like Chicxulub

  1. Dust and aerosols ejected high into the atmosphere, preventing sunlight from reaching the Earth

  2. Insulating the Earth from solar radiation and causing global temperatures to fall for a few years

  3. Greenhouse gases (CO2, water, and CH4) caused by the impactor and its ‘target rocks’ remaining in the atmosphere and causing global temperatures to increase for decades
• Temperature rises can affect agriculture, sea levels, and the frequency of extreme weather incidents
• BGS is committed to research aimed at slowing down the effects of a changing climate and helping society become resilient to climate change
• Meteorite impacts

  • Chicxulub crater, Yucatán Peninsula in Mexico
• The carbon cycle describes the process where carbon atoms travel from the atmosphere into the Earth and back into the atmosphere
• Temperature rise causes oceans to release more CO2 into the atmosphere


  Causing the temperature to rise again
• Carbon capture and storage involves capturing carbon dioxide at emission sources, transporting, and storing it underground
• Quantity of CO2 in the atmosphere increases

  Temperature of the Earth rises
• Gases in the Earth’s atmosphere act as an insulating blanket, trapping more of the Sun’s heat
• Feedback


  • A process where changes in one factor lead to additional and enhanced or reduced changes in others
  • Positive feedback accelerates a temperature rise, negative feedback slows it down
• Topics related to climate change in geography

  • Weather
  • Causes of climate change
  • Real-world examples
  • Effects on people and the planet
• Climate change is explored in geography in relation to weather, causes, real-world examples, and impacts on people and the planet
• Climate change refers to changes in the climate on a long-term time scale
• Key takeaways from Climate Change Geography

  • Climate change definition
  • Causes of climate change
  • Effects of climate change
  • Evidence for climate change
• Test your knowledge with multiple choice flashcards on Climate Change Geography
• Climate change is a very relevant topic and is discussed a lot across subjects
• Components of climate change

  • Global temperatures
  • Other climatic components
• There is no evidence of global warming