Climate Change Biology A In 2005, an ice core showed that CO2 levels in the troposphere are the highest they have been in 650,000 years.

CLIMATE CHANGE VS. GLOBAL WARMING  In recent years, experts have changed their discussions from the topic of “global warming” to “climate change”  This is because global warming suggests a constant increase in temperature, while climate change includes all major changes in weather patterns.  Climate change explains increases in hurricanes and flooding ALONG WITH major snow storms and below normal temperatures.

PAST CLIMATE AND THE GREENHOUSE EFFECT  Over the past 900,000 years, the planet has experienced prolonged periods of global cooling and global warming.

Major Greenhouse Gases  A greenhouse gas is any gas that traps heat within the earth’s atmosphere, rather than allowing it to escape as it otherwise would.  Increases in average concentrations of 3 greenhouse gases between 1860 and 2004, mostly due to fossil fuel burning, deforestation, and agriculture.

CLIMATE CHANGE AND HUMAN ACTIVITIES  Evidence that the planet is warming, mostly because of human actions: The 20 th century was the hottest century in the past 1000 years. The 20 th century was the hottest century in the past 1000 years. Since 1900, the earth’s average temperature has risen 0.6 C° Since 1900, the earth’s average temperature has risen 0.6 C° Over the past 50 years, Arctic temperatures have risen almost 2x as fast as those in the rest of the world. Over the past 50 years, Arctic temperatures have risen almost 2x as fast as those in the rest of the world. Glaciers and floating sea ice are melting and shrinking at increasing rates. Glaciers and floating sea ice are melting and shrinking at increasing rates. During the last century, the world’s sea level rose by cm During the last century, the world’s sea level rose by cm

EFFECTS OF CLIMATE CHANGE  Between 1979 and 2005, average Arctic sea ice dropped 20% (as shown in blue hues above).

EFFECTS OF CLIMATE CHANGE  Rising Sea Levels: If seas levels rise by 9-88cm during this century, most of the Maldives islands and their coral reefs will be flooded.

EFFECTS OF CLIMATE CHANGE  In a warmer world, agricultural productivity will be altered  Crop and fish production in some areas could be reduced by rising sea levels  Global warming will increase deaths from: Heat and disruption of food supply Heat and disruption of food supply Spread of tropical diseases to temperate regions Spread of tropical diseases to temperate regions

Global warming may harm human health November 16, 1998 Climatic changes related to global warming could foster dangerous outbreaks of cholera, dengue fever and malaria, …

Study: Global warming spurs migrations Thursday, January 2, 2003 Rising global temperatures that have lured plants into early bloom and birds to nest earlier in the spring are altering the ranges and behavior of hundreds of plant and animal species worldwide, two studies conclude.

Report: Coral bleaching hits record level May 19, 1999 Global warming has been linked to an unprecedented episode of coral bleaching in 1998, …

Vicious cycle: Global warming feeds fire potential November 2, 2000 Global warming may greatly accelerate the fire cycle in the desert ecosystem of North America, according to a study published today in the journal Nature. Elevated carbon dioxide levels, the result of increased fossil fuel burning, can alter the delicate balance of grasses in desert areas, the report notes. This finding may have major implications for the biodiversity and health of desert ecosystems in the western United States.

Top Greenhouse Emitters  19.1 % - United States  9.9% - China  5.1% - India  4.3% - Brazil  3.8 % - Germany  3.7% - Japan  2.4% - United Kingdom  1.9% - Indonesia  1.7% - Italy

Reducing CO 2 Emissions Drive a fuel-efficient car, walk, bike, carpool, and use mass transit Use energy-efficient windows Use energy-efficient appliances and lights Heavily insulate your house and seal all drafts Reduce garbage by recycling and reuse Insulate your hot water heater Use compact fluorescent bulbs Plant trees to shade your house during summer Set water heater no higher than 49°C (120°F) Wash laundry in warm or cold water Use low-flow shower head Buy products from companies that are trying to reduce their impact on climate Demand that the government make climate change an urgent priority What Can You Do?