Chapter 8 – The Biosphere Greenhouse Effect

Greenhouse Usually, a greenhouse is used to control climate and farm something regardless of the external conditions Ex: it is winter but the inside is still warm How do we keep the inside warm?

Global Warming Def’n: A gradual increase in the overall temperature of the Earth’s atmosphere, generally attributed to increased levels of certain pollutants Greenhouse Effect Def’n: A natural process that allows the Earth to retain some heat it receives from the sun Without the greenhouse effect, the Earth would be much colder (-18°C)

Greenhouse Effect Sunlight goes through the atmosphere (some is reflected into space) Earth’s surface absorbs sun’s energy and heats up The ground emits infrared rays that is sent to the atmosphere Greenhouse gasses (GHGs) trap some IR rays and reflect them back to Earth, which heats up the Earth (some IR rays escape into space)

Pollutants CO2, CH4 and N2O N2O: used in fertilizer and created from combustion from car engines H2O (clouds) also contribute to the greenhouse effect (but is not a pollutant per se)

Greenhouse Gases (Pollutants) Water vapour (H2O), usually in the form of clouds Not a pollutant per se Carbon dioxide (CO2), major byproduct of combustion Methane (CH4), agriculture and farm animals contribute the most Nitrous oxide (N2O), mainly due to nitrogen-rich fertilizer and car engines CO2 levels have increased greatly due to human activity but CH4 is significantly more potent (21x greater than CO2)

6M sea level rise would submerge all in red

Negative side effects of global warming Drought Rising sea level Fires Disrupted ecosystems Melting ice caps Thawing of permafrost

Permafrost Def’n: a thick subsurface layer of soil that remains frozen through the year, occurring chiefly in arctic regions In some areas, the top layer of the permafrost, called the active layer, thaws only in the summer. The lower layer remains frozen. Plants can grow during this sort period of time The rise in global temperature has caused the permafrost to begin to thaw

Consequences Land above it sinks or changes shape, causing roads, buildings, pipes and infrastructure to be damaged Organic matter trapped in permafrost decomposes and releases CO2 and CH4 2a: Methane trapped in ice is released https://www.youtube.com/watch?v=FM0hczFNDZI

Zombie Anthrax https://www.washingtonpost.com/news/morning- mix/wp/2016/07/28/anthrax-sickens-13-in-western- siberia-and-a-thawed-out-reindeer-corpse-may-be-to- blame/?utm_term=.6e5f5adea992

Consequences 4- Landslides can occur 5- Soil erosion (it wears down) and impacts plant and animal life

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