Context: With more greenhouse gases trapping heat, average annual global temperatures are rising. This is known as global warming. While temperatures have risen since the end of the Pleistocene, 10,000 years ago, this rate of increase has been more rapid in the past century, and has risen even faster since 1990. The 10 warmest years in the 134-year record have all occurred since in the 21st century, and only one year during the 20th century (1998) was warmer than 2013, the 4th warmest year on record (through 2013) (Figure 1.1). The 2000s were the warmest decade yet. Annual variations aside, the average global temperature increased about 0.8o C (1.5o F) between 1880 and 2010, according to the Goddard Institute for Space Studies, NOAA. This number doesnt seem very large. Why is it important? The United States has long been the largest emitter of greenhouse gases, with about 20% of total emissions in 2004. As a result of Chinas rapid economic growth, its emissions surpassed those of the United States in 2008. However, its also important to keep in mind that the United States has only about one-fifth the population of China. Whats the significance of this? The average United States citizen produces far more greenhouse gas emissions than the average Chinese person. The following images show changes in the Earth and organisms as a result of global warming: Figure 1.2, Figure (a) Breakup of the Larsen Ice Shelf in Antarctica in 2002 was related to climate warming in the region. (b) The Boulder Glacier has melted back tremendously since 1985. Other mountain glaciers around the world are also melting. The timing of events for species is changing. Mating and migrations take place earlier in the spring months. Species that can are moving their ranges uphill. Some regions that were already marginal for agriculture are no longer arable because they have become too warm or dry. What are the two major effects being seen in this animation? Glaciers are melting and vegetation zones are moving uphill. If fossil fuel use exploded in the 1950s, why do these changes begin early in the animation? Does this mean that the climate change we are seeing is caused by natural processes and not by fossil fuel use? Permafrost is melting and its extent de- creasing. There are now fewer summer lakes in Siberia. (a) Melting ice caps add water to the oceans, so sea level is rising. Remember that water slightly expands as it warms this expansion is also causing sea level to rise. (b) Weather is becoming more variable with more severe storms and droughts. Snow blanketed the west- ern United States in December 2009. (c) As surface seas warm, phytoplankton productivity has decreased. (d) Coral reefs are dying worldwide; corals that are stressed by high temperatures turn white. (e) Pine beetle infestations have killed trees in western North America The insects have expanded their ranges into areas that were once too cold. Warming temperatures are bringing changes to much of the planet, including California. Sea level is rising, snow pack is changing, and the ecology of the state is responding to these changes. Click image to the left or use the URL below. URL: 
 Question: warmer temperatures are causing coral reefs to
Output: turn white.