Unit 5 Part 4 - Impacts of Climate Change

2014 - the IPCC Put out their 5th assessment

Sea Level Rise

• Water expands when it heats up.
• Ice melting is increasing in volume
• 1.5-4.5 degrees Celsius can lead to 15-95cm of rise
• If a threshold is hit…it could be meters

Ocean Acidification

• Increased carbon dioxide absorption by the ocean has made it slightly acidic
• Oceans absorb about 1/2 of anthropogenic carbon dioxide
• We are at a .1 pH rise but remember that scale is logarithmic
• As oceans warm…they absorb less carbon dioxide

Polar Ice Cap Melting

• Ice on Antarctica, glaciers and Greenland will increase sea level when melted but not Arctic Ice.
• Loss of the Greenland Ice sheet could stop the Thermohaline conveyor by diluting the super salty water needed to push it along.
• That would dramatically alter Europe’s climate.
• Methane now trapped under the arctic ice sheets would be released and contribute to GHG levels.

Glaciers

• Glaciers in the last 30 years have been decreasing significantly
• Loss of glaciers lead to flooding and landslides
• Glaciers are a vital source of water for billions of people

Weather Patterns

• More heat means more energy for more violent and more extreme weather. Current weather patterns can shift.
• Global Precipitation can increase up to 15% in some areas, but other areas will have extended droughts.
• These changes in water movement will lead to more erosion, desertification and salinization of lands.

Food Issues

• Though temperatures increasing should increase photosynthesis, this is not necessarily the case because extra respiration is required to NPP may not increase

Biodiversity

• Animals CAN move
• However, plants cannot move fast enough to flee global warming
• Plants are breaking dormancy too early and could die from a late frost because of false spring
• If water temperature hits 72 degrees, coral will die

Human Health

• More heat waves, cold snaps, hurricanes, floods and other natural weather disasters will kill or injure more people
• But…warmer temperatures would lead to less colds, reduced heating bills and lower accidental driving deaths on snowy roads