responces to future warming

• What are the main uncertainties in global carbon cycle projections?

  Natural factors, human factors, and feedback mechanisms
• How do carbon sinks function in the carbon cycle?

  They absorb more carbon from the atmosphere than they release
• What could potentially cause carbon sinks to become carbon sources?

  A decrease in net inward flux of carbon into sinks
• What is the effect of CO2 fertilization on terrestrial ecosystems?

  It may increase the photosynthesis rate, accelerating carbon influx
• What happens when permafrost melts in tundra regions?

  It triggers methanogenesis, releasing methane into the atmosphere
• How does drying of peatlands affect carbon emissions?

  It allows increased decay, releasing CO2 into the atmosphere
• How much carbon is stored in permafrost and peat in tundra regions?

  1,700 PgC
• What is the impact of higher CO2 concentrations in oceans?

  It fertilizes phytoplankton, accelerating the biological pump
• How does warming ocean temperatures affect carbon absorption?

  It decreases the ocean's capacity to absorb CO2
• What is the effect of ocean acidification on marine life?

  It may lead to increased mortality of molluscs and crustaceans
• How does economic growth in developing countries affect carbon emissions?

  It requires increased energy consumption, leading to higher carbon emissions
• What is the predicted economic growth rate for developing countries?

  1. 10% per annum
• What is the predicted economic growth rate for emerging countries?

  1. 6% per annum
• What is the predicted economic growth rate for developed countries?

  2% per annum
• How might new nationalism and protectionism affect carbon emissions?

  They may reverse globalization, leading to reduced output and lower carbon emissions
• What could superpower tensions lead to in terms of energy pathways?

  They may interrupt energy pathways, driving up energy prices and reducing carbon emissions
• How does population growth in developing countries affect carbon emissions?

  It raises carbon influx through forest clearance and fossil fuel combustion
• What is the predicted peak population according to the UN?

  9 billion in 2050
• What are unconventional fossil fuel sources mentioned in the study material?

  Tar sands, fracking, and deep water oil sources
• How might the expansion of renewable energy sources affect carbon emissions?

  It may reduce outward carbon flux from energy generation
• What is the role of feedback mechanisms in the carbon cycle?

  They may amplify or dampen increases in atmospheric carbon concentration
• What is methanogenesis?


  It is the release of methane through partial decay in saturated conditions
• What is a tipping point in the context of the carbon cycle?

  It is a threshold leading to abrupt, large-scale change
• What did the IPCC 2014 Report identify regarding tipping points?


  Seven possible tipping points that could lead to large-scale release of stored carbon
• How does warming of the Arctic affect thermohaline circulation?

  It may lead to influx of fresh water, slowing or halting thermohaline circulation
• What is the impact of slowing thermohaline circulation on carbon absorption?

  It reduces the rate at which ocean water saturated with carbon is removed from the surface
• What are Milankovitch cycles?

  They affect the shape of Earth’s orbit, altering incoming solar radiation
• What is the significance of solar cycles in climate change?

  They vary solar energy output, potentially producing global warming and cooling
• What are carbon-temperature uncertainties?

  They relate to the poorly understood interactions between thermohaline circulation and atmospheric temperatures
• What is the effect of atmospheric oscillations like El Niño on climate?

  They produce significant changes in regional temperatures and precipitation patterns
• Why is it difficult to isolate the effect of increasing carbon concentrations on temperature change?

  Due to poorly understood natural drivers of temperature change
• What was the CO2 concentration in 1960?

  316 ppm
• What was the CO2 concentration in 2015?

  400 ppm
• What was the annual increase in CO2 concentration from 2010 to 2015?

  It increased by 3.05 ppm/yr in 2015
• What was the annual increase in CO2 concentration in 2005?

  1. 52 ppm/yr
• What was the CO2 concentration in 2000?

  369 ppm
• What was the CO2 concentration in 1990?

  354 ppm
• What was the CO2 concentration in 1980?

  338 ppm
• What was the CO2 concentration in 1975?

  331 ppm
• What was the CO2 concentration in 1970?

  325 ppm