Environmental Science 102
Weather vs. Climate
Weather – current state of the atmosphere
Climate – aggregate atmospheric conditions; long-term average weather
How do we measure global temperature?
Average of all temperature record measurements.
Proxy Temperature Records
Data from sources which do not give actual temp. – provide an inferred temperature
Biological Proxy Records: tree rings, pollen, floral and faunal distributions, fossils
Geological Proxy Records: sediment/glacial deposits, ice cores, minerals, geochemistry
Chemical Proxy Records: O18/O16 ratios (ice and foram shells)
Sea level is not constant
Changes on a daily basis:
Changes on an annual basis:
Is the world actually getting warmer?
“Warming of the climate system is unequivocal… The atmosphere and oceans have warmed, the amounts of snow and ice have diminished, sea level has risen, and the concentration of greenhouse gases have increased.” – IPCC 2013: Climate Change 2013: The Physical Science Basis.
The Evidence of Global Warming
Make note of each piece of evidence, and what that evidence shows:
What are the 4 main pieces of evidence for global warming?
Ten Signs of a Warming World - NOAA web site
Causes of Climate Change
Natural Causes or Human Induced Causes?
Changes in amounts of incoming vs. outgoing radiation results in global warming or cooling.
Factors controlling amount of insolation: