How we know what we know about climate change
Post on 13-Jul-2015
108 Views
Preview:
Transcript
Nathan Hobbs Becca Hatheway
Lisa Gardiner
HOW DO WE KNOW WHAT WE KNOW?
USING CLIMATE SCIENCE AS A VEHICLE TO INCREASE STUDENT CONFIDENCE IN SCIENTIFIC DATA AND
INTERPRETATION
Doran 2009
WHAT PERCENTAGE OF CLIMATE SCIENTISTS AGREE THAT THE EARTH IS WARMING AND HUMANS ARE THE CAUSE?
WHAT PERCENTAGE OF THE U.S. PUBLIC AGREE THAT THE EARTH IS WARMING AND HUMANS ARE THE CAUSE?
Earth is warming.
Humans have been the main cause of warming over the past 60 years (95-100% prob).
The amounts of CO2, methane, and nitrous oxide are higher than they ’ve been for 800,000 years.
If we reduce emissions we can limit future warming, however some warming is inevitable.
WHAT DO WE KNOW?
The Intergovernmental Panel on Climate Change 1000s of climate scientists from around the world and representatives from
world nations, an effort coordinated by the United Nations.
IPCC 5 th Assessment Report – The Physical Science Basis
Released September 2013
Includes the current state of understanding of climate and climate change (and how we know what we know about climate).
SAYS WHO?
WORKSHOP ACTIVITIES
Ways of knowing about climate Classroom Activities
Climate models Model Resolution
Paleoclimate proxies Oxygen Isotopes
Instrumental record Matching Data and Meaning
What is a climate model?
Global climate models (GCMs) use mathematical equations to describe the behavior of factors of the Earth system that impact climate
Climate scientist perspective on confidence in climate models
ABOUT CLIMATE MODELING
Scenarios of Future Carbon Dioxide Global Emissions and Concentrations
Nakićenović, N. and R. Swart (eds.), 2000: Appendix VII: Data tables. In: Special Report on Emissions Scenarios
MODEL RESOLUTION
Step 1: Tape gr id paper to top of container ( lower or higher resolut ion gr ids).
Step 2: Poke skewers through paper at the intersections.
Step 3: Try to determine the shape of the legos in the bottom of the box based on the height of the skewers. Mark this shape on blank gr id paper.
Step 4: Compare shapes between high and low resolut ion gr ids.
Step 5: After you’re done… check the bottom of the box to see the shape of the legos!
MODEL RESOLUTION ACTIVITY
PALEOCLIMATOLOGY: AN INVESTIGATION
What is a proxy?
Resolution vs. Span
Examples of proxies
Ice cores
Tree rings
Pollen
Speleothems
Coral
Historical documents
The Water Cycle, Oxygen-18, and Ice Cores
INDIRECT CLUES ABOUT PAST CLIMATES ARE KNOWN AS PALEOCLIMATE PROXIES, OR
PROXY RECORDS
Just as Sherlock Holmes might infer the height, weight
and other telltale features of a suspect from a series of
footprints, paleoclimatologists infer the climatic
conditions of the past from tree rings, ice cores, layers
of ocean sediments, and similar proxy evidence.
(Randy Russell, Spark: UCAR Science Education)
TWO FACTORS ARE USED TO DESCRIBE TYPES OF PALEOCLIMATE PROXY DATA
Span – how far back in time the record allows us to peer.
Tree ring records span the most recent few thousands of years.
Ice core records go back as much as hundreds of thousands of years.
Fossils can be up to hundreds of millions of years old.
Resolution – the level of detail of a proxy record.
Tree ring data can have an annual resolution.
Ocean sediments, on the other hand, often have resolutions on the order of a century because sediments are mixed by currents and burrowing marine life, blending short-term trends.
SOME TYPES OF PROXIES
Speleothems : the chemistry of l imestone deposits provide clues to past climate
Tree rings : the thickness of rings is an indicator of growing season conditions.
Coral : chemistry of skeletal layers provides clues to past climate.
Pollen: the variety of plant species (identified from pollen), combined with information about the climate where those species typically thrive, provides clues to past climate
And also …
ICE CORES
http://michigantoday.umich.edu/2009/11/vostok-graph.jpg
VIDEO: ICE CORE SECRETS COULD REVEAL ANSWERS TO GLOBAL WARMING
VIDEO: DEMO OF O-16 AND O-18 PHYSICAL MODEL
PC1 VS. TEMPERATURE GREENLAND 1829-1970
R² = 0.497
-8.000
-6.000
-4.000
-2.000
0.000
2.000
4.000
6.000
8.000
-16 -14 -12 -10 -8 -6 -4 -2 0 2
PC
1
Average Temperature ( C)
PC1 valuesLinear (PC1 values)
On your table
Graphs of data from the instrumental record of climate and global change from the IPCC 5th Assessment Report.
Statements that are supported by the graphed data
Statements that are not supported by graphed data
Match each graph with the statement that it supports.
(Note: This activity is a prototype and we’d like your feedback.)
MATCHING DATA AND MEANING
ADDITIONAL RESOURCES
Learn more about climate science at spark.ucar.edu
For workshop resources: spark.ucar.edu/workshops
Becca Hatheway – hatheway@ucar.edu
Lisa Gardiner – lisagard@ucar.edu
Thank you for coming!
MORE SPARK WORKSHOPS
Cooking Up Weather in the Primary Classroom
Friday, 8-9am Room MHB-2A
Computer Games, Simulations, & Virtual Labs
Saturday, 11-12pm, Room MHB-4B
Weather Headlines
Saturday, 11-12pm, Room MHB-2B
CLIMATE CHANGE: A TEACHING PERSPECTIVE
Jeff KiehlSenior Scientist
National Center for Atmospheric Research
Thursday, 3:30-4:30Convention Center Room 103/105
Overview of the findings of the recent Fifth Assessment Report of the Intergovernmental Panel on Climate Change and discussion of the basic
science.
top related