Consequences of Climate Change - T. RIDER & F.M. WALTER FEBRUARY 2022 - Spring 2022
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SSO 102: Welcome to the Anthropocene Consequences of Climate Change T. RIDER & F.M. WALTER FEBRUARY 2022
There is alarming evidence that important tipping points, leading to
irreversible changes in major ecosystems and the planetary climate
system, may already have been reached or passed. Ecosystems as diverse
as the Amazon rainforest and the Arctic tundra, for example, may be
approaching thresholds of dramatic change through warming and drying.
Mountain glaciers are in alarming retreat and the downstream effects of
reduced water supply in the driest months will have repercussions that
transcend generations. Climate feedback systems and environmental
cumulative effects are building across Earth systems demonstrating
behaviours we cannot anticipate.
- UNEP Intergovernmental Panel on Climate Change Report
Source: IPCC Fourth Assessment Report: Climate Change 2007, Intergovernmental Panel on Climate Change. Source: Le Quéré, C. et al. (2013). The global carbon budget 1959-2011.
http://www.watchblog.com/republicans/archives/008095.html * In 2019, the US emitted 5,130 million metric tons of energy-related carbon dioxide
Health Effects of CO2
Ppm CO2 Duration Comment/effect
6 hours Poor indoor air quality may be noticeable
5,000 hours NASA limit for long term spaceflight
10,000 minutes Drowsiness
12,000 Headaches reported
20,000 Minutes Poor indoor air quality noticeable
>20,000 Minutes-hours Difficulty breathing; possible acidosis
30,000 Minutes Breathing rate doubled
50,000 Minutes 4x normal breathing rate; toxic threshold.
>50,000 Minutes Unconsciousness; death
Source: https://inspectapedia.com/hazmat/Carbon_Dioxide_Hazards.php
Do you think recent changes in climate and weather are more attributed to natural or human causes? Why? If you feel humans are the main cause of global warming, do you think you contribute to global warming, and if so, how? Where do you stand on what the U.S. government should be doing about global warming and climate change ?
• A warmer atmosphere
holds more water.
Effects on • Energy release from H2O
condensation drives
Weather
weather.
• Atmospheric circulation
patterns changeH2O and Increasing T⊕ • Relative humidity (RH): amount of water air can hold at a given temperature relative to saturation • Absolute humidity (AH): amount of water in the air – units: gm/m3 or kg/kg • At a fixed RH, a 1oC increase in T increases AH by ~7%
Is climate change causing more extreme weather?
More severe storms
• Increased erosion
• Weaker jet stream/steering currents
Consequences
Longer droughts
of Extreme
Weather Damage from storms
More wildfiresA buoy sits on the dry and cracked bed of what used to be Shasta Lake in California.
Report from the UN Office for the Coordination of Humanitarian Affairs (OCHA): “In 2012, there were 905 natural catastrophes worldwide—and 93 percent of these events were weather-related disasters". (Worldwatch) "Climate disasters are. . . up from around 50 percent from two decades ago. These disasters take a heavier human toll and come with a higher price tag. In the last decade, 2.4 billion people were affected by climate-related disasters, compared to 1.7 billion in the previous decade. The cost of responding to disasters has risen tenfold between 1992 and 2008. (OCHA)”
A record number of hurricanes, wildfires and floods exacerbated by climate change cost the world $210 billion in damage in 2020, Munich Re - a top insurer - said. Damages totaled $95 billion in the U.S., nearly double the losses in 2019. The country experienced a record number of Atlantic hurricanes and the largest wildfires on record in California in 2020, the second- hottest year on record.
• Higher average global
precipitation, with some parts of
the earth becoming dryer while
Some others become wetter.
• A rise in sea level of 0.09 to 0.88
Results of meters by 2100.
Climate • Changes in regional climate and
vegetation.
Change • Changes in the productivity of
agricultural lands.
• Increases in the intensity and
severity of tropical storms.• Rain and temperatures
affect crop yields
Effects on • Irrigation raises surface salt
Agriculture levels
• All desert civilizations based
on irrigation have failedPredicted global temperatures in the next century
Source: https://www.climate.gov/news-features/understanding-climate/climate-change-global-temperature-projectionsIn oceans
• Anoxia
• Sea life migrates towards poles
Consequences • Weakening of conveyor system
of Increasing
On land
Temperatures
• “habitation zones” migrate
poleward
• Flora/fauna must adjustSea Level through 2017
Mean sea level rising 3.3 ± 0.4 mm/yr (NASA)
Source: https://www.climate.gov/Contributions to Sea Level Rise
Sea Level Rise • 3.5 mm/yr • Causes: – Thermal expansion – Melting glaciers/ice caps • Rate expected to continue and accelerate • Total increase: 0.8 – 2m – up to 7m if Greenland ice cap melts
• Flooding of cities/low lying land
– 5 million Americans live within 4 ft of high
tide line
Consequences – 634 million live within 9m of sea level
of Sea Level • Increased coastal erosion
• Increased storm-surge flooding in storms
Rise • Disappearance of low-lying island nations
• Climate Refugees
• Note: continents are rising too
– Rebound from last ice ageFlood mitigation
Economic Relocating agriculture
Effects
Fisheries decliningOceanic Acidity • Ocean water is naturally basic, with pH=8.2 (averaged over the past 300 million years) • Atmospheric CO2 is in chemical equilibrium with the oceans, meaning some CO2 is absorbed. – About 25% of anthropogenic CO2, 22 megatons/day, is absorbed • CO2 absorbed in H2O forms carbonic acid, H2CO3 • Current ocean pH has decreased to 8.1 – This is a 25% increase in pH in 200 years – pH could decrease to 7.7 by 2100
Source: NOAA
Reduces concentration of CO3- -
Calcium carbonate (CaCO3) is the
principal ingredient in shells (limestone)
Consequences
Carbonic acid dissolves CaCO3
of Ocean
Acidity Affects metabolism of marine organisms
Most mass extinctions coincide with
times of oceanic acidificationHuman Contribution to CH4 • https://www.nytimes.com/interactive/2019/12/12/climate/tex as-methane-super-emitters.html
Consequences of Global Climate Change: Global circulation patterns change
Basic Atmospheric Circulation – no rotation (Hadley cells)
Terrestrial Winds
Consequences of Global Climate Change: The Poles are Warming (faster than the equator)
Arctic Sea Ice is Thinning Interactive chart: https://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/
Increasing Temperatures • In oceans • On land
Larsen C Ice Shelf Calving
Source: NASA; 11/10/16
Area: 5000 km2; 10% of ice shelf See also NY Times 2/7/17Upsala Glacier, Argentina
3 oC temperature rise since 1980 Note meltwater ponds/streams 79N drains 15% of Greenland’s interior Source: https://www.bbc.com/news/science-environment-54127279
Consequences of Global Climate Change: • Global circulation patterns change • Decrease in equatorial-polar gradient will weaken trade winds and jet stream.
The Polar Vortex A stable polar vortex requires a strong jet and a large latitudinal temperature gradient
Ocean Circulation
• Speeds generally increasing (Gulf Stream an exception)
• Increased surface winds the cause?
S. Hu et al., Sci Adv, 6:eaax7727, 2020.ENSO
El Nino – Southern Oscillation
• Possible 11 year period
• Possible correlation with cosmic ray flux
• Possible driver:
– Emergence of new magnetic field every solar cycle (11 years)
• First posited in 1987 (Labitzke, K. GRL 14, 535)
– Phasing wrong for solar UV irradiance/stratospheric heating
Correlation is not causation
• Leamon, R.J. et al. 2020, JGR Space Physics (submitted)Earth’s past:
RCP4.5: 2oC temperature rise by 2100;
Requires negative CO2 emissions
RCP8.5: 4oC temperature rise by 2100;
Possible is no reduction in CO2 emissions
Cognition vs CO2 level
Source: Karnauskas, K.B. et al. 2020, GeoHealth, https://doi.org/10.1029/2019GH000237Disruption of societies
Relocation from low-lying areas
Human Starvation
Costs
Extreme weather
Climate RefugeesNet Effect of Rapid Climate
Change
Not GoodWill the actions we take today be enough to forestall the
direct impacts of climate change? Or is it too little too
late?
Will taking action make our lives better or safer, or will it
only make a difference to future generations?
How will measures to cut carbon emissions affect my life
in terms of cost?
Thought
Given that renewable sources provide only a small
Questions percentage of our energy and that nuclear power is so
expensive, what can we realistically do to get off fossil
fuels as soon as possible?
Will the remedies to climate change be worse than the
disease? Will it drive more people into poverty with
higher costs?
So finally, doing what needs to be done to combat
climate change all comes down to political will?You can also read
