SPR-696: Preliminary Study of Climate Adaptation for the Statewide ...

Source: National Oceanic and Atmospheric Administration (NOAA), 2011.Figure 4. Atmospheric Carbon Dioxide at Mauna Loa ObservatoryFigure 5 shows that the observed global mean temperature over land and ocean also hasincreased over the same time period. The year 2010 tied with 2005 as the warmest year sincerecordkeeping began in 1880. The annual global combined land and ocean surface temperaturewas 1.12°F above the 20th century average. The 2010 combined land and ocean surfacetemperature in the Northern Hemisphere also was the warmest on record, while the combinedland and ocean surface temperature in the Southern Hemisphere was the sixth warmest suchperiod on record. Warming trends over the 20th century are documented for nearly all locationsthat have sufficient data, except the North Atlantic Ocean near Greenland and Iceland, and thesoutheastern United States.The magnitude of the enhanced greenhouse effect is influenced by various complex interactionsin the earth-ocean-atmosphere system. Many processes and feedback loops must be accountedfor in order to realistically project climate changes resulting from particular GHG emissionscenarios. These complications are the source of much of the debate that has occurred about thelikely magnitude and timing of climate changes due to the enhanced GHG effect. Nevertheless,the scientific community has near-consensus that these global trends tend toward more frequentor severe effects in the future.11