1. Seasonal Changes in Sea Ice Area Presented by Rob Snyder

2. Earths Cryosphere consists of all forms of water in the solid state and includes: Sea Ice Lake Ice SnowGlaciers Ice Cap Sheet Ice Permafrost Ice in Clouds

3. Sea Ice Formation Ways to explore the seasonal changes in the extent of sea ice area include: Interpreting graphsInterpreting graphs Working with modelsWorking with models Viewing images and animationsViewing images and animations Hands-on activitiesHands-on activities Research activitiesResearch activities

4. Interpreting Sea Ice Area Graphs Half of you will interpret a graph for the Southern Hemisphere. Half of you will interpret a graph for the Northern Hemisphere. Note: Later this week, you will actually make sea ice.

5. The Northern Hemisphere group will interpret this graph. http://arctic.atmos.uiuc.edu/cryosphere/

6. The Southern Hemisphere group will interpret this graph.

7. When was the maximum of sea ice area for the entire Earth during the last 365 days?

8. Maximums and minimums of the sea ice area graphs correspond closely with the changes in Astronomical seasons in both Hemispheres. http://okfirst.mesonet.org/train/meteorology/Seasons.html

9. Why would the sea ice minimum in the Northern Hemisphere occur around the time of a Fall Equinox rather than around the time of a Summer Solstice? Why would the sea ice minimum in the Northern Hemisphere occur around the time of a Fall Equinox rather than around the time of a Summer Solstice?

10. This graph reveals the pattern of change in the length of daytime. Is this a graph for the Northern or Southern Hemisphere? http://www.eoearth.org/article/Earth-Sun_relationships_and_insolation

11. During the entire summer, the lengths of daytimes are greater than the lengths of nighttimes. The altitude of the sun is also higher during summer months During the entire summer, the lengths of daytimes are greater than the lengths of nighttimes. The altitude of the sun is also higher during summer months http://www.azsolarcenter.com/design/pas-2.html

12. This years Northern Hemispheres Autumnal Equinox and the Southern Hemispheres Vernal Equinox will begin at 20:18 UT (16:18 EDT) on September 22nd. Why does that happen at one specific moment in time?

13. A Globe Walk activity/demonstration provides an opportunity for students to use models to: A Globe Walk activity/demonstration provides an opportunity for students to use models to: Develop an understanding of the seasonal changes in the altitude of the sun and the lengths of daytimes in the Polar Regions. Develop an understanding of the seasonal changes in the altitude of the sun and the lengths of daytimes in the Polar Regions. Develop an understanding of how the time and dates are determined for the changes of the astronomical seasons. Develop an understanding of how the time and dates are determined for the changes of the astronomical seasons.

14. Views of the extent of sunlight in the Polar Regions as the seasons change.Views of the extent of sunlight in the Polar Regions as the seasons change. The location on Earth where the midday sun is directly overhead as the seasons change.The location on Earth where the midday sun is directly overhead as the seasons change. http://aa.usno.navy.mil/data/docs/earthview.php A United States Naval Observatory web site can be used to provide:

15. What are some additional questions that could be posed that relate to the sea ice area graphs?

16. Research Activities Use images from web sites to monitor snow cover and sea ice in the Polar Regions and at lower latitudes during the school year.Use images from web sites to monitor snow cover and sea ice in the Polar Regions and at lower latitudes during the school year. Use archives on web sites to compare the present accumulation of sea ice and snow with past years and with normal years.Use archives on web sites to compare the present accumulation of sea ice and snow with past years and with normal years.

17. The Cryosphere Todays web site can be used to compare the extent of sea ice and snow cover in both hemispheres. (The color scale applies only to the extent of sea ice.) http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=11&fd=15&fy=2008&sm=02&sd=15&sy=2009

18. Building an Understanding of the Seasonal Changes in Sea Ice Area Investigate a wide range of implications of changes in the climate of the Polar Regions. Conduct both short term and long term investigations. Utilize a wide range of resources. Continue the development of essential investigative skills and scientific knowledge.