Ashley Fisher,Brittany Olson, Maile Gove, Matt Griffin, and Brad Elmendorf.
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Transcript of Ashley Fisher,Brittany Olson, Maile Gove, Matt Griffin, and Brad Elmendorf.
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
Pressure
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
Little Ice Age
Sunspots Since1600
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 40,000-50,000 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-climate-change.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/