Global Warming History Geography Learning Outcome Identify the

Global Warming History & Geography Learning Outcome Identify the context of geography and history on global warming Describe some possible consequences Explain personal and other groups perspectives

The Role of the Sun’s Energy in the Past Changes in the sun’s intensity have influenced Earth’s climate in the past. For example, the so-called “Little Ice Age” between the 17 th and 19 th centuries may have been partially caused by a low solar activity phase from 1645 to 1715, which coincided with cooler temperatures.

Key argument of skeptics is that it has been warmer in the past – so why worry?

Changes in Earth’s orbit have had a big impact on climate over tens of thousands of years. These changes appear to be the primary cause of past cycles of ice ages, in which Earth has experienced long periods of cold temperatures

"Scientific evidence for warming of the climate system is unequivocal. " - Intergovernmental Panel on Climate Change The current warming trend is of particular significance because most of it is very likely human-induced and proceeding at a rate that is unprecedented in the past 1, 300 years.

Describe and explain what these graphs show Is there a pattern?

Consensus: 97% of climate scientists agree Temperature data from four international science institutions. All show rapid warming in the past few decades and that the last decade has been the warmest on record.

What do you think the effects of global warming will be? • In a group make a list of possible effects of global warming, think about – Environmental effects – Effects on Kazakhstan – Effects on developed countries – Effects on poor countries

Geographic Effects Sea level rise Global sea level rose about 17 centimeters (6. 7 inches) in the last century. The rate in the last decade, however, is nearly double that of the last century.

Global temperature rise Major global surface temperature reconstructions show that Earth has warmed since 1880. Most of this warming has occurred since the 1970 s, with the 20 warmest years having occurred since 1981 and with all 10 of the warmest years occurring in the past 12 years. Even though the 2000 s witnessed a solar output decline resulting in an unusually deep solar minimum in 2007 -2009, surface temperatures continue to increase.

Warming oceans The oceans have absorbed much of this increased heat, with the top 700 meters (about 2, 300 feet) of ocean showing warming of 0. 302 degrees Fahrenheit since 1969.

Shrinking ice sheets The Greenland Antarctic ice sheets have decreased in mass. Data from NASA's Gravity Recovery and Climate Experiment show Greenland lost 150 to 250 cubic kilometers (36 to 60 cubic miles) of ice per year between 2002 and 2006, while Antarctica lost about 152 cubic kilometers (36 cubic miles) of ice between 2002 and 2005.

• Glacial retreat • Glaciers are retreating almost everywhere around the world — including in the Alps, Himalayas, Andes, Rockies, Alaska and Africa.

• Extreme events • The number of record high temperature events in the United States has been increasing, while the number of record low temperature events has been decreasing, since 1950. The U. S. has also witnessed increasing numbers of intense rainfall events.

Which of these effects are the most important in your opinion? • • • Sea level rise Ice sheet loss Extreme weather events Temperature rise Sea temperature rise

The current and future consequences of global change " The evidence indicates that the costs and damage of climate change are likely to be significant and to increase over time. “ IPCC Think about the people who have lost their homes.

• Some of the regional impacts of global change forecast by the IPCC: • North America: Decreasing snowpack in the western mountains; 5 -20 percent increase in yields of rain-fed agriculture in some regions; increased frequency, intensity and duration of heat waves in cities that currently experience them. • Latin America: Gradual replacement of tropical forest by savannah in eastern Amazonia; risk of significant biodiversity loss through species extinction in many tropical areas; significant changes in water availability for human consumption, agriculture and energy generation. • Europe: Increased risk of inland flash floods; more frequent coastal flooding and increased erosion from storms and sea level rise; glacial retreat in mountainous areas; reduced snow cover and winter tourism; extensive species losses; reductions of crop productivity in southern Europe. • Africa: By 2020, between 75 and 250 million people are projected to be exposed to increased water stress; yields from rain-fed agriculture could be reduced by up to 50 percent in some regions by 2020; agricultural production, including access to food, may be severely compromised. • Asia: Freshwater availability projected to decrease in Central, South, East and Southeast Asia by the 2050 s; coastal areas will be at risk due to increased flooding; death rate from disease associated with floods and droughts expected to rise in some regions. •

Compare the maps. Describe the common things. Think about patterns places people affected