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Download The Little Ice Age
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The Ashley Fisher ,Brittany Olson, Maile Gove, Matt Griffin, and Brad Elmendorf • • • • • • • Overview/Situation Evidence of the Little Ice Age Possible Causes of the Little Ice Age Current Predictions Crops Suggestions Questions Problem Statement • We are trying to analyze where funds should go for producing the worlds crops based on past and current climate records. We will be using the little ice age as a model for researching this issue. Situation • The International Commission on Economics (ICE) wants us to research where they should invest R & D funds for planning for agricultural needs for the next century. Evidence of the Little Ice Age • Paintings • Disease • Ice Cores • Temperature Records Gabriele Bella (1733-99) – This painting is of a portion of a lagoon in Venice that froze over Possible Causes of the Little Ice Age • • • • • • Volcanic Activity Surface Albedo Milankovitch theory Solar Activity North Atlantic Oscillation Natural Causes Volcanic Activity • 1815 – Tambora (Indonesia) • 1835 – Coseguina (Nicaragua) • 1883 – Krakatau (Indonesia) Surface Albedo • Albedo – the fraction of light that is reflected back into space and is not absorbed by the Earth. • Zero – all sunlight is absorbed • One – no sunlight is absorbed Milankovitch Theory http://www.homepage.montana.edu/~geol445/hyperglac/time1/milankov.htm Milankovitch Theory http://www.homepage.montana.edu/~geol445/hyperglac/time1/milankov.htm Milankovitch Theory http://www.homepage.montana.edu/~geol445/hyperglac/time1/milankov.htm ‘Normal’ Positive North Atlantic Oscillation Low Pressure over Iceland High Pressure Over the Azores = Mild, Humid Air in Europe ABNORMAL Negative North Atlantic Oscillation High Pressur e Low Pressure Cold, Dry Weather in Europe What Are Sunspots? • Sunspots are dark spots on the surface of the sun where intense magnetic activity takes place. • Sunspots prevent hot gasses from the interior of the star reaching the surface • The overall effect of sunspots is positive. The sun emits more light • The disappearance of sunspots makes for a cooler sun • When sunspot activity is at a minimum it is also referred to as Maunder Minimum Maunder Minimum • Sunspots cause occasional ferocious eruptions of electrified gas and light • More sun spots usually means an increase in solar activity • During Maunder Minimum the sun expands and its rotation is slowed How did sunspots play a role in the little ice age? • Although there is no official cause of the little ice age, many scientists speculate that it was due mostly in part to low sunspot activity • Maunder Minimum was at its height from 1645 to 1715 • Sunspots could be seen by the astronomers of the day, such as Galileo Sunspots Since 1600 Little Ice Age Current Sunspots During Little Ice Age Continued • Maunder Minimum caused a colder sun which also meant the sun would send out less warmth to the earth • During one 30-year span inside the little ice age astronomers observed only 50 sunspots • Whereas today astronomers see 40,00050,000 sunspots in 30-year periods • During the little ice age the sun dropped in temperature by around ¼ of a percent Gabriele Bella (1733-99) – This painting is of a portion of a lagoon in Venice that froze over The Effect of the Little Ice Age on Crops • Seasons changed by 15-20% • Growing period shortened to 1-2 months • The worst of the 17th Century famines Crops • Genetically Altered crops • GRACE • Depletion of the worlds Aquifers Improbable Causes of the Little Ice Age – Volcanoes – The increased volcanic activity didn’t start until 1800’s – Surface Albedo – Causes an increase in the cooling of the earth due to ice and snow, but the increased amount of snow needs to be there beforehand. – Ocean Atmosphere Conveyor System – This would have caused a more localized effect while the Little Ice Age was global Probable Causes of the Little Ice Age • Low sunspot activity – would cause a global cooling because less radiation from the sun • The natural cycles of the earth that have not yet been discovered. Natural Cycles • Little Ice Ages are inevitable • Sediments and Ice Cores support this theory • Over the last 10,000 years, changes have occured • Suggests: There is a natural cooling and warming of the earth about every 1,500 years. Predictions • Another Little Ice Age is most likely, but when? • Ice Core samples show trends and speed • European continent and North Atlantic Current- most affected • Severity? CO2 levels? Recommendations • Increase genetic research on crops so that they can withstand temperature changes and lengths of growing seasons. • Build greenhouses to hold the more unstable crops. • Move crops south towards equator • Have less production of crop in Europe Questions? Resources • http://www.atmos.washington.edu/1998Q4/211/project2/group4.htm • http://www.scientificamerican.com/article.cfm?id=how-are-past-temperatures • http://holocene.meteo.psu.edu/shared/articles/littleiceage.pdf • http://www2.sunysuffolk.edu/mandias/lia/little_ice_age.html • http://www.eh-resources.org/timeline/timeline_lia.html#maunder http://arstechnica.com/science/news/2009/08/another-little-ice-age-solar-activity-and-climatechange.arshttp://www.space.com/scienceastronomy/sunspot_record_041027.html • http://www.eh-resources.org/timeline/timeline_lia.html http://www.atmos.washington.edu/1998Q4/211/project2/group4.htm • http://www.bbc.co.uk/dna/h2g2/A781715 • http://vulcan.wr.usgs.gov/Volcanoes/Indonesia/description_krakatau_1883_eruption.html • http://www2.hawaii.edu/~jmaurer/albedo • http://eosweb.larc.nasa.gov/HPDOCS/misr/misr_html/global_seasonal_albedo.html • http://www.homepage.montana.edu/~geol445/hyperglac/time1/milankov.htm • http://www2.sunysuffolk.edu/mandias/lia/little_ice_age.html • http://www.grida.no/publications/other/ipcc_tar/?src=/climate/ipcc_tar/wg1/070.htm • http://earthobservatory.nasa.gov/Newsroom/NasaNews/Agriculture2009/ • http://earthobservatory.nasa.gov/Features/WeighingWater/weighing2.php • http://www.atmos.washington.edu/1998Q4/211/project2/group4.htm • http://www.eh-resources.org/timeline/timeline_lia.html • http://www.ldeo.columbia.edu/res/pi/NAO/
