Climate Change

Climate Change

Kim Weborg-BensonSUNY FredoniaDept. of Geosciences

Katrina

August 28

Seasonal Records Set in 2005Most 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 20th-century 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 coreFrom 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 sheetsDuring 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.

Eccentricity 100,000 yr cycle

Variations in the shape of Earth’s Orbit

Obliquity 41,000 yr cycle

Variations in the Tilt of Earth’s Axis

Precession 23,000 yr cycle

Variations in “Wobble” of Earth’s Axis

Milankovitch Cycles and Glaciation

Insolation – amount of solar radiation reaching an area or the Earth

Looking at thecomposition of airbubbles in a corefrom 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 CarbonDioxide

CO2 as measured at Mauna Loa Observatory

Atmospheric CO2 - Weekly DataMauna Loa Observatory | NOAA-ESRL Data

Week Atmospheric CO2 

March 24-30, 2013 397.92 ppm 

March 24-30, 2012

395.30 ppm (1 year ago)

March 24-30, 2003

377.06 ppm (10 years ago)

Atmospheri CO2 - Increase Since 1Mauna Loa Observatory | NOAA-ESRL Data

As of Increase Since 1800 

March 24-30, 2013 + 116.03 ppm

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 globally-averaged 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

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.

Greenland Ice Sheet

Melting Glacial IceContributes 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