Transcript AOSS_NRE_480_L10_Forcing_Internal_Variability_20140218.ppt

Climate Change: The Move to Action
(AOSS 480 // NRE 480)
Richard B. Rood
Cell: 301-526-8572
2525 Space Research Building (North Campus)
[email protected]
http://aoss.engin.umich.edu/people/rbrood
Winter 2014
February 18, 2014
Class News
• Ctools site: AOSS_SNRE_480_001_W14
• Something I am playing with
– http://openclimate.tumblr.com/
Politics of
Dismissal Entry
Model
Uncertainty
Description
Projects
• Fracking (Omar, Jeffrey, Austin, Megan, Ranya)
– With the recent technological advances in hydraulic fracturing,
the U.S. has become the world’s largest producer of oil and is
projected to become an exporter of natural gas. Natural gas has
been posed as a “bridge fuel” to displace coal in the production
of electricity, and to reduce the emissions of carbon dioxide. As
a policy advisor on climate change, I need to know whether or
not a transition to natural gas serves to reduce the emissions of
greenhouse gases and the impact on water resources. I am
especially concerned about the leakage of methane and huge
amount of water that is required. I have another team working
on public health effects air quality and water quality are out of
your domain.
Projects
• Agricultural (Edwin, Rachel, Kathleen, Chris)
– The accounting of greenhouse gas emissions from agriculture is
difficult. I have read that something like 30% of the total
emissions are agriculturally related. This requires that those
emissions used in, say, fertilizer manufacturing are accounted in
agriculture rather than industry. Recently, I read a blog
http://www.wunderground.com/blog/RickyRood/greenhouseemissions-of-agriculture that said there was one group who
claimed all by itself, livestock was responsible for more than 52%
of the emissions. This seems enormous and challenges many
conventional strategies for greenhouse gas management. The
CEO of my company has announced a sustainability effort, and I
want to know what decisions my food manager can make the
matter to climate change, including water resources. Should I
emphasize vegetarian meals, or is it better to buy local,
“sustainable,” or organic?
Projects
• Air Travel (Meng, Arnav, Mason, John, Justin)
– There is no doubt that airplanes emit carbon dioxide and other
greenhouse gases. Air travel is an important part of the
economy. When I read about air travel and climate impacts, the
information is complicated. Often the discussion ends with the
admission that there are not obvious options to make air travel
and transport “sustainable” in the sense of climate change. The
European Union has been considering a way to reduce
emissions from air travel. Their efforts have only revealed even
more complexity in reducing the environmental impact of aircraft.
In order to know how much priority to give to sustainable air
travel in my research and development portfolio, I need a
knowledge-based assessment of the impact of air travel on
climate, risks associated with “doing nothing” and the viable
strategies for making air travel “sustainable.”
Today
• Scientific investigation of the Earth’s
climate: Foundational information
– Changes in Forcing
– “Internal Variability”
– In Class Exercise: Response
• It hasn't warmed since 1998: For the years 19982005, temperature did not increase. This period
coincides with society's continued pumping of
more CO2 into the atmosphere.
Let’s start with this figure
• We arrived at this rather complex figure at
the end of the previous lecture
1998
Climate Forcing
(-2.7, -0.6)
2001
Hansen et al: (1998) & (2001)
(-3.7, 0.0)
Today
• Scientific investigation of the Earth’s
climate: Foundational information
– Changes in Forcing
– “Internal Variability”
– In Class Exercise: Response
• It hasn't warmed since 1998: For the years 19982005, temperature did not increase. This period
coincides with society's continued pumping of
more CO2 into the atmosphere.
Let’s look at just the last 1000 years
Surface temperature and CO2 data from the
past 1000 years. Temperature is a northern
hemisphere average. Temperature from
several types of measurements are consistent
in temporal behavior.
{
Note that on this scale, with more time
resolution, that the fluctuations in
temperature and the fluctuations in CO2
do not match as obviously as in the
long, 350,000 year, record.
This is a span of time with very
“stable” climate, by historical records.
Stable meaning, low variability. Also it
has been warm.
Sources of internal variability
• There is “natural” variability.
– Solar variability
– Volcanic activity
– Internal “dynamics”
•
•
•
•
Atmosphere - Weather
Ocean
Atmosphere-ocean interactions
Atmosphere-ocean-land-ice interactions
• “Natural” does not mean that these modes of variability
remain constant as the climate changes. Separation of
“natural” and “human-caused.”
Energy doesn’t just come and go
• The atmosphere and ocean are fluids.
The horizontal distribution of energy,
causes these fluids to move. That is
“weather” and ocean currents and the
“general circulation.”
• “General circulation” is the accumulated
effect of individual events.
Transport of heat poleward by atmosphere and oceans
• This is an important part of the climate
system
• One could stand back far enough in
space, average over time, and perhaps
average this away.
• This is, however, weather ... and weather
is how we feel the climate day to day
– It is likely to change because we are changing
the distribution of average heating
Some Aspects of Climate Variability
• One of the ways to think about climate
variability is to think about persistent patterns
of weather
– Rainy periods
• Floods
– Dry periods
• Droughts
• During these times the weather for a region
does not appear random – it perhaps
appears relentless
Cold
Messy
Warm
Cold
Messy
Temperature
An example of variability: Seasons
Winter
Summer
Rain
comes in
fronts
Rain comes in
thunderstorms
Winter
Forced variability
responding to
solar heating
Wave Motion and Climate
Internal Variability?
• Weather – single “events” – waves, vortices
• There are modes of internal variability in the
climate system which cause global changes.
– El Nino – La Nina
• What is El Nino
– North Atlantic Oscillation
• Climate Prediction Center: North Atlantic Oscillation
– Annular Mode
– Inter-decadal Tropical Atlantic
– Pacific Decadal Oscillation
Atmosphere-Ocean Interaction: El-Nino
Changes during El Nino
Times series of El Nino (NOAA CPC)
EL NINO
LA NINA
OCEAN TEMPERATURE
EASTERN PACIFIC
ATMOSPHERIC
PRESSURE
DIFFERENCE
Some good El Nino Information
• NOAA Climate Prediction: Current El Nino
/ La Nina
• NOAA CPC: Excellent slides on El Nino
– This is a hard to get to educational tour. This
gets you in the middle and note navigation
buttons on the bottom.
GISS Temperature 2002
1997-98 El Nino
January 2011 Temperature Anomalies
Internal Variability?
• Weather – single “events” – waves, vortices
• There are modes of internal variability in the
climate system which cause global changes.
– El Nino – La Nina
• What is El Nino
– North Atlantic Oscillation
• Climate Prediction Center: North Atlantic Oscillation
– Annular Mode
– Inter-decadal Tropical Atlantic
– Pacific Decadal Oscillation
North Atlantic Oscillation
Positive Phase
U.S. East, Mild and Wet
Europe North, Warm and Wet
Canada North & Greenland, Cold and Dry
Negative Phase
U.S. East, Cold Air Outbreaks, Snow (dry)
Europe North, Cold; South, Wet
Greenland, Warm
North Atlantic Oscillation Phase
(from Climate Prediction Center)
January 2011 Temperature Anomalies
Year-to-Year Changes in Winter Temperatures
Differences Relative to 1961-1990 Average
Late 1970s
2006-2011
From Jim Hurrell
Internal Variability?
• Weather – single “events” – waves, vortices
• There are modes of internal variability in the
climate system which cause global changes.
– El Nino – La Nina
• What is El Nino
– North Atlantic Oscillation
• Climate Prediction Center: North Atlantic Oscillation
– Annular Mode
– Inter-decadal Tropical Atlantic
– Pacific Decadal Oscillation
Pacific Decadal Oscillation
•
Does the Pacific Decadal Oscillation operate
regularly lasting 20-30 years, and does
southern California experience droughts during
that period?
•
•
The Pacific Decadal Oscillation is one of several
“oscillations” that are important to weather and climate.
Some attributes of the Pacific Decadal Oscillation
Pacific Decadal Oscillation: Basics
Colors: Sea Surface Temperature difference from long term average.
Arrows: Stress on the ocean surface caused by winds
Warm here
Better version of figure from JISAO
Cool here
Some information on Pacific Decadal Oscillation
• Joint Institute for Study of Atmosphere and
Ocean (JISAO):
– Pacific Decadal Oscillation
• Climate Prediction Center (CPC):
– 90 Day Outlook Summary
– Weather and Climate Linkage
• National Climatic Data Center (NCDC):
– Decadal Oscillations
• Review Paper from Rood Class References
– Mantua and Hare (2002) J of Oceanography
Bumps and Wiggles
• Rood’s Series on Bumps and Wiggles
Today
• Scientific investigation of the Earth’s
climate: Foundational information
– Changes in Forcing
– “Internal Variability”
– In Class Exercise: Response
• It hasn't warmed since 1998: For the years 19982014, temperature did not increase. This period
coincides with society's continued pumping of
more CO2 into the atmosphere.
Lean and Rind, Next 20 years
GISS Temperature 2002
1997-98 El Nino
An interesting time to study?
In Class Exercise
• Economist:
– Temperature not going up, but carbon dioxide is.
Look! Warming has stopped.
Iconic and Fundamental Figures
Scientific investigation of Earth’s climate
SUN: ENERGY, HEAT
EARTH: ABSORBS ENERGY
EARTH: EMITS ENERGY TO SPACE  BALANCE
Sun-Earth System in Balance
SUN
EARTH
PLACE AN
INSULATING
BLANKET
AROUND
EARTH
The addition to the
blanket is CO2
FOCUS ON
WHAT IS
HAPPENING
AT THE
SURFACE
EARTH: EMITS ENERGY TO SPACE  BALANCE
Increase of Atmospheric Carbon Dioxide (CO2)
Primary
increase comes
from burning
fossil fuels –
coal, oil,
natural gas
Data and more information
Temperature and CO2: The last 1000 years
Surface temperature and CO2 data from the
past 1000 years. Temperature is a northern
hemisphere average. Temperature from
several types of measurements are consistent
in temporal behavior.
 Medieval warm period
 “Little ice age”
 Temperature starts to follow CO2 as CO2
increases beyond approximately 300 ppm,
the value seen in the previous graph as the
upper range of variability in the past
350,000 years.
The Earth System
SUN
CLOUD-WORLD
ATMOSPHERE
ICE
(cryosphere)
OCEAN
LAND
Radiation Balance Figure
Radiative Balance (Trenberth et al. 2009)
1998
Climate Forcing
(-2.7, -0.6)
2001
Hansen et al: (1998) & (2001)
(-3.7, 0.0)