Transcript The Little Ice Age

The
Ashley Fisher ,Brittany Olson,
Maile Gove, Matt Griffin, and
Brad Elmendorf
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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
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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
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http://www.atmos.washington.edu/1998Q4/211/project2/group4.htm
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http://www.scientificamerican.com/article.cfm?id=how-are-past-temperatures
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http://holocene.meteo.psu.edu/shared/articles/littleiceage.pdf
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http://www2.sunysuffolk.edu/mandias/lia/little_ice_age.html
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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
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http://www.eh-resources.org/timeline/timeline_lia.html
http://www.atmos.washington.edu/1998Q4/211/project2/group4.htm
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http://www.bbc.co.uk/dna/h2g2/A781715
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http://vulcan.wr.usgs.gov/Volcanoes/Indonesia/description_krakatau_1883_eruption.html
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http://www2.hawaii.edu/~jmaurer/albedo
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http://eosweb.larc.nasa.gov/HPDOCS/misr/misr_html/global_seasonal_albedo.html
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http://www.homepage.montana.edu/~geol445/hyperglac/time1/milankov.htm
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http://www2.sunysuffolk.edu/mandias/lia/little_ice_age.html
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http://www.grida.no/publications/other/ipcc_tar/?src=/climate/ipcc_tar/wg1/070.htm
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http://earthobservatory.nasa.gov/Newsroom/NasaNews/Agriculture2009/
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http://earthobservatory.nasa.gov/Features/WeighingWater/weighing2.php
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http://www.atmos.washington.edu/1998Q4/211/project2/group4.htm
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http://www.eh-resources.org/timeline/timeline_lia.html
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http://www.ldeo.columbia.edu/res/pi/NAO/