An iceberg melts in Kulusuk, Greenland, near the Arctic Circle.
•Global warming is a rise in
global temperatures that
could result from the
of radiation due to higher
•50% of all radiation that reaches the Earth is
absorbed. The remaining 50% is reflected back
out to space.
•The greenhouse effect is
the natural heating of
Earth’s surface caused by
the retention of heat by
certain atmospheric gases
called greenhouse gases.
•Scientists theorize that any
increase in the amount of
greenhouse gases, particular
carbon dioxide (CO2), would
result in the increased
4. Some of
The Atmosphere reflects
the sun’sheat is
5) On Earth:
Energy that passes
absorbed by the
ground, water, gases,
•A portion of the solar
radiation that reaches
the Earth’s surface
such as ice, snow, and
ocean are reflected.
Radiation trigger the
gases togases to
move.aAs a result,the
As result, the
atmosphere is heated.
Consequences of Global Warming:
Unless we act now, your children will inherit a hotter world, dirtier
air and water, more severe floods and droughts, and more wildfires.
ecosystem shifts and species die-off
b. drought and
c. more intense
Greater evaporation as a result of global warming
could increase the risk of wildfires.
a. deadly heat
waves and the
Greater evaporation as a result of global
could increase the risk of wildfires.
More frequent and more intensive heat waves could
result in more heat-related deaths. Photo: Gary Braasch,
Chicago, July 1995. See the
World View of Global Warming website for more Gary
Braasch photos illustrating the consequences of the
a. more powerful hurricanes
b. melting glaciers
c. sea-level rise
The satellite photo at far left shows the Larson B ice shelf on Jan. 31, 2002. Ice appears as solid
white. Moving to the right, in photos taken Feb. 17 and Feb. 23, the ice begins to disintegrate. In the
photos at far right, taken Mar. 5 and Mar 7, note water (blue) where solid ice had been, and that a
portion of the shelf is drifting away. Photos: National Aeronautics and Space Administration
Ancient ice shelf breaks free
A giant ice shelf the size of 11,000 football fields has snapped free from Canada's
Arctic, scientists said. The mass of ice broke clear 16 months ago from the coast
of Ellesmere Island.
•Jacques Descloitres, MODIS Rapid Response Team, NASA/GSFC
The Arctic’s largest ice shelf is breaking up. The Ward
Hunt Ice Shelf is a remnant of the compacted snow and
ancient sea ice that extended along the northern shores
of Ellesmere Island in Northern Canada until the early
a. ecosystem shifts and
Warmer temperatures may cause some
ecosystems, including alpine meadows
in the Rocky Mountains, to disappear.
For more Environmental Facts:
Natural Resources Defense Council
This file photo provided by
Mary Sage shows a polar
bear watching a whaling
crew off shore near Barrow,
Alaska, Monday, May 22,
2006. Polar bears are in
deep trouble because of
global warming and other
factors and deserve federal
protection under the
Endangered Species Act,
the Bush administration is
proposing Wednesday, Dec.
27, 2006. (AP
Photo/Courtesy of Mary
Sage, Joseph Napaaqtuq
Polar Bears are dying at alarming rates due to Global Warming.
Blue Man Group – Earth to America (Global Warming) 1:49 min
How Do Ice Cores of Glaciers Tell Us about Past Climates?
•Research scientists collect and study glacial ice cores.
•Data from these ice cores provide one of the most
complete records of past climate conditions. Of greatest
interest are the deep cores obtained by drilling programs in
Summit, Greenland and Vostok, Antarctica.
•The Vostok ice core provides the longest continuous
record of Antarctic climatic history.
•Analysis of the core has been completed to a depth of
3350 meters, representing approximately 440,000
years of climate history.
story of Earth's
layers of the
core tell the
Scientists can determine the amount of carbon dioxide
that was in the air during different time periods by
analyzing gas bubbles trapped in ice cores. Carbon
dioxide is a greenhouse gas that plays a major role in the
atmosphere’s energy balance.
Scientists can reconstruct a record of temperatures that
occurred in the past by analyzing the ratio of oxygen isotopes
trapped within air bubbles in the ice (O16 & O18).
The graph below shows how the temperature has changed over
the past 165,000 years. The graph shows temperature
anomalies—variations in the temperature above or below
Vostok’s present day average temperature of -56ºC.
Temperature and carbon dioxide data are plotted together
on this graph. This makes it easier to compare the two
variables and how they may be related.
Recent Changes in Atmospheric Carbon Dioxide
Scientists have been precisely measuring the amount of
carbon dioxide in the atmosphere since 1958. The results
of these studies are plotted on the graph below. The
yearly average CO2 level is represented by the smooth
black line, and seasonal changes appear as small peaks
Ice core research projects are working to extend the record of
global climate further back in time and over more of Earth’s
To learn about their most recent discoveries, visit the links
Explore these links for more information about ice core
projects and climate research:
Graph of Vostok ice core data extending back for 400,000 years
Greenland Ice Sheet Project 2
North Greenland Ice Core Project
Taylor Dome Ice Core Project
European Project for Ice Coring in Antarctica (EPICA)
World Data Center for Paleoclimatology
Collection of photographs about polar ice core research
National Ice Core Laboratory