Transcript Climate Change PowerPointx

Climate Change
Kim Weborg-Benson
SUNY Fredonia
Dept. of Geosciences
Katrina
August 28
Seasonal Records Set in 2005
Most tropical storms: 28. Old record: 21 in 1933.
Most hurricanes: 15. Old record: 12 in 1969.
Most Category 5 hurricanes: 4 (Emily, Katrina, Rita, and Wilma). Emily was upgraded to
Category 5 upon re-analysis. Old record: 2 in 1960 and 1961.
Most hurricane names to be retired: 5 (Dennis, Katrina, Rita, Stan, Wilma, and possibly
others). Previous record: 4 in 1955, 1995, and 2004.
Most major hurricanes to hit the U.S.: 4 (Dennis, Katrina, Rita, Wilma). Previous record:
3 in 1893, 1909, 1933, 1954, and 2004.
Most damage ever recorded in a hurricane season: $150 billion. Previous record:
approximately $50 billion dollars (normalized to 2005 dollars) set in 1992 and 2004.
Highest Accumulated Cyclone Energy (ACE) index: 245. Previous record: 243 (1950).
Average for a season is 93.
Latest end to a hurricane season: January 6 Previous record: January 5, for the 1954-55
hurricane season.
This NOAA satellite image taken Monday, Oct. 29, 2012 shows Hurricane Sandy off
the Mid Atlantic coastline moving toward the north with maximum sustained winds
of 90 mph.
The Empire State Building towers in the background of an apartment buliding in Chelsea, New
York City, with the facade broken off October 30, 2012 the morning after Hurricane Sandy
(Photo by TIMOTHY A. CLARY/AFP/Getty Images)
Homes in Fenwick Island, Del. are surrounded by floodwaters from Hurricane Sandy on
Tuesday, Oct. 30, 2012. Officials said Fenwick Island and nearby Bethany Beach appeared to be
among the hardest-hit parts of the state. (AP Photo/Randall Chase)
Water floods the street near Layton's Monday, Oct. 29, 2012, in Ocean City, Md.
This photo provided by 6abc Action News shows the Inlet section of Atlantic City, N.J., as
Hurricane Sandy makes it approach, Monday Oct. 29, 2012.
Vehicles are submerged on 14th Street near the Consolidated Edison power plant, Monday, Oct.
29, 2012, in New York.
In 2009, a Rasmussen poll showed
that only 46 percent of Americans
thought climate change was a serious
issue.
In 2010, Gallup reported that 48
percent of Americans thought that
the seriousness of global warming was
exaggerated.
___________________________________
• A poll conducted by Rasmussen on
Monday, Nov. 5, 2012, showed:
• Of the 1,000 likely voters surveyed, 68
percent said they thought climate
change is a somewhat serious or very
serious problem, while 30 percent of
respondents said it was not a serious
problem.
The Benenson Strategy Group conducted 800 telephone interviews
nationwide from February 2, 2013 through February 5, 2013 on behalf of
the League of Conservation Voters. All respondents were registered
voters who voted in the 2012 general election. The margin of error for
the entire sample is ±3.5% at the 95% confidence level.
An overwhelming majority of American
voters view climate change as a real
and tangible problem with 61% saying
the effects of climate change are already
affecting them personally or will in their
lifetime.
Weather – state of the
atmosphere at a given place and
time
Climate – a composite of weather
“climate is what you expect,
weather is what you get”
According to
NOAA scientists,
the globally
averaged
temperature for
February 2013
tied with 2003 as
the ninth
warmest
February since
record keeping
began in 1880.
It also marked
the 28th
consecutive
February and
336th
consecutive
month with a
global
temperature
above the 20thcentury average
The seafloor sediments are full of fossilized microscopic shells whose chemistry can
reveal ocean temperatures that existed tens of thousands of years ago. (Photo by
Tom Kleindinst, Woods Hole Oceanographic Institution)
How is Climate Change Detected?
Sea Floor Sediment
Oxygen-isotope analysis :
This analysis measures the ratio between
16O (common) and 18O (heavier) in ocean water.
There is more 18O in water during glacial times.
There is more 16O in water during interglacial times.
Working with a core
From Antarctica
How is Climate Change Detected?
Glacial Ice:
– Scientists collect ice cores with a drilling
rig.
– Ice cores contain a detailed record of
changing air temperatures and snow fall.
– They also contain air bubbles trapped in the
ice, which contain a record of variations in
atmospheric composition.
How is Climate Change Detected?
Rocks:
• Rocks reflect the environment
in which they formed so record
changing environments and
climate
Sediment deposited by a Glacier
Maximum extent of Ice sheets
During the Pleistocene
Map of Glacial Deposits
Why are there Ice Ages?
Ice Ages are rare in Geologic History
And, what explains the temperature
fluctuations during the last ice age?
The Greenhouse Effect and CO2
Milutin
Milankovitch
Milankovitch Cycles
• Milankovitch cycles describe the
changes in the way the earth orbits the
sun. These changes combine to affect
the amount and seasonal variation of
solar radiation reaching the Earth and
can define the sequence of ice ages and
warm periods.
Variations in the shape of Earth’s Orbit
Eccentricity
100,000 yr cycle
Variations in the Tilt of Earth’s Axis
Obliquity
41,000 yr cycle
Variations in “Wobble” of Earth’s Axis
Precession
23,000 yr cycle
Milankovitch Cycles and Glaciation
Insolation – amount of solar radiation reaching an area or the Earth
Looking at the
composition of air
bubbles in a core
from Antarctica
Climate-Feedback Mechanisms
– When one component of climate system is
altered, scientists must consider how it relates
to other components
– The effects of positive-feedback mechanisms
reinforce the initial change.
– Increase temperature
– Increase evaporation
– Increase atmospheric CO2
– Increases temperature
Two differences with Climate
change today
• 1. CO2 is being added by burning of
fossil fuels
Increases
in
Atmospheric
Carbon
Dioxide
CO2 as measured at
Mauna Loa Observatory
Week
Atmospheric CO2
March 24-30, 2013
397.92 ppm
March 24-30, 2012
395.30 ppm
(1 year ago)
Atmospheric CO2 - Weekly Data
Mauna Loa Observatory | NOAA-ESRL Data
March 24-30, 2003
377.06 ppm
(10 years ago)
As of
Increase Since 1800
March 24-30, 2013
+ 116.03 ppm
Atmospheri CO2 - Increase Since 1Mauna
Loa
Observatory | NOAA-ESRL Data
Two differences with Climate
change today
1. CO2 is being added by burning of fossil
fuels
2. Timing
450,000 years
vs. 130 years
According to NOAA scientists, the globallyaveraged annual combined land and ocean
surface temperature in 2012 was 1.03°F (0.57°C)
above the 20th-century average of 57.0°F
(13.9°C).
The annual report also found that all 12 years of
the 21st century (2001-2012) rank among the 14
warmest in the 133-year period of record.
Climate-Feedback Mechanisms: Decline in Sea Ice
Arctic Sea Ice Decreased by 20% from 1979-2005
Satellite data reveal how the new record low Arctic sea ice extent,
from Sept. 16, 2012, compares to the average minimum extent over the past
30 years (in yellow). Sea ice extent maps are derived from data captured by the Scanning Multichannel
Microwave Radiometer aboard NASA's Nimbus-7 satellite and the Special Sensor Microwave Imager on
multiple satellites from the Defense Meteorological Satellite Program. Credit: NASA/Goddard Scientific Visualization Studio
Thermohaline Circulation
• When sea ice forms,
cold, salty water sinks (because it is more
dense).
This carries CO2 into the deep water
where it is stored
The formation of seasonal sea ice removes CO2
from the atmosphere
Climate-Feedback Mechanisms
– Warmer temperatures
– Less seasonal sea ice
– Less CO2 taken out of atmosphere
– More CO2 in Atmosphere
– Warmer temperatures
– Less seasonal sea ice
Other Effects of Climate Change
Changes in Precipitation
Melting
Glaciers
Muir Glacier in Alaska
Greenland
The longest observed mountain glacier in Greenland
Greenland Ice Sheet
Fig. HTC19. Monthly unsmoothed values of the total mass (in Gigatons, Gt),
of the Greenland ice sheet from GRACE. On the horizontal axis, each year
begins on 1 January. Each small + symbol is a monthly value.
Melting Glacial Ice
Contributes to Rising Sea Levels
Global Ocean Heat Content
and Sea Level
Past and projected global average sea level. The gray shaded area shows the estimates of sea level change
from 1800 to 1870 when measurements are not available. The red line is a reconstruction of sea level change
measured by tide gauges with the surrounding shaded area depicting the uncertainty. The green line shows
sea level change as measured by satellite. The purple shaded area represents the range of model projections
conducted by IPCC for a medium growth emissions scenario (IPCC SRES A1B) and excludes the additional rise
in sea level if Greenland or Antarctica contribute more ice to the oceans in the future. Source: IPCC (2007)
A nine member panel, led by M.I.T. meteorologist Jule Charney, was appointed by the
National Academy of Sciences to undertake a rigorous study of global warming
• Their conclusions: “If carbon dioxide continues to increase the study
group finds no reason to doubt that climate changes will result and no
reason to believe these changes will be negligible. For a doubling of
carbon dioxide from pre-industrial levels, the likely global temperature rise
will be between 2.5 and 8 degrees Fahrenheit”.
• “the climate system has a built in time delay so the temperature rise could
take several decades”
• “for this reason, what might seem like the most conservative approach,
waiting for evidence of warming in order to assess the models’ accuracy,
actually amounts to the riskiest possible strategy”
• “We may not be given a warning until the CO2 loading is such that an
appreciable climate change is inevitable
“waiting for evidence of warming in order
to assess the models’ accuracy, actually
amounts to the riskiest possible strategy”
• Ad Hoc Study Group on Carbon Dioxide and Climate (1979)
This figure shows projected greenhouse gas concentrations for four different emissions scenarios. The top
three scenarios assume no explicit climate policies. The bottom green line is an illustrative “stabilization
scenario,” designed to stabilize atmospheric carbon dioxide concentration at 450 parts per million by volume
(ppmv). Source: USGCRP (2009)
Bars depict number of named systems (open/yellow),
hurricanes (hatched/green), and category 3 or greater (solid/red), 1886-2004
TEMPERATURE ANOMALIES FOR YEARS 2002 - 2011
Learn from the past, look to the future
Thank you