Transcript Climate
Climate and Climate Science Current News & Weather Is Climate Changing? Weather vs. Climate Climate System Cryosphere For Next Class: Read Chapter 2 (pp. 33-50). Reminder: Labs WILL meet next week! 2016 Hottest Year Globally https://www.washingtonpost.com/news/energyenvironment/wp/2017/01/18/u-s-scientistsofficially-declare-2016-the-hottest-year-on-recordthat-makes-three-in-arow/?utm_term=.9ca670f96f84 Italy Avalanche https://www.washingtonpost.com/world/dangerous -conditions-hamper-search-for-victims-at-avalanchestricken-italian-hotel/2017/01/20/8037e78c-de9911e6-8902-610fe486791c_story.html?hpid=hp_hpmore-top-stories_italyavalanche430am%3Ahomepage%2Fstory&utm_term=.bb75b8 34b439 Global Climate Change Is the climate changing? On what evidence (i.e., what are the indicators of climate change? Overview of Observed Change Indicators IPCC 2013 Indicators of Climate Change IPCC 2013 IPCC 2013 IPCC 2013 IPCC 2013 Climate Science Highly interdisciplinary field drawing on expertise from: • • • • • • • Atmospheric Science Geography Chemistry Physics Biology/Ecology Remote sensing and computer science Economics, Demography, and other social sciences Main Drivers of Climate Change IPCC 2013 What is the difference between Weather and Climate? What is the difference between Weather and Climate? Weather: State of the atmosphere over the short term (minutes to ~15 days). Climate: Synthesis of weather conditions in a given area, characterized by long-term statistics (mean values, variances, probabilities of extreme values, etc.) of the meteorological elements in that area. Climate is what you expect, weather is what you get! What is meant by the climatic norm? Defining Climate The Climatic Norm • Encompasses the total variation in the climate record, that is, both averages plus extremes © AMS 23 Defining Climate Historical Perspectives • First North American systematic weather observations made in 1644-1645 at Old Swedes Fort (now Wilmington, DE) • U.S. Surgeon General James Tilton issued an order 2 May 1814 to begin the establishment of a national network of weather and climate observing stations • National network of volunteer observers who mailed monthly weather reports to the Smithsonian was established in the mid-1800s © AMS 24 The Climate System System: entity whose components interact in an orderly manner according to the laws of physics, chemistry, and biology Earth’s Climate System: defined as the totality of the atmosphere, hydrosphere, cryosphere, biosphere and geosphere and their interactions © AMS 25 The Climate System Atmosphere • Relatively thin envelope of gases and tiny suspended particles surrounding the planet • Divided into four layers: © AMS Troposphere Stratosphere Mesosphere Thermosphere 26 What is the Cryosphere? What is the Cryosphere? Consists of various forms of frozen water at the planet’s surface. What are some components of the Cryosphere? Components of the Cryosphere Snow – a collection of loosely bonded ice crystals deposited from the atmosphere. Sea ice – any form of ice found at sea which has originated from the freezing of sea water. Glaciers – fallen snow that, over many years, compresses into large, thickened ice masses that move. Ice Sheet – mass of glacial land ice extending more than 50,000 square kilometers (20,000 square miles). The Greenland and Antarctic Ice Sheets are the only two that currently exist. Ice Shelves – thick slab of ice, attached to a coastline and extending out over the ocean as a seaward extension of an ice sheet or series of glaciers. Iceberg – massive piece of ice of greatly varying shape, protruding 5 m or more above sea-level, which has broken away from a glacier and which may be afloat or aground.