Paleoclimate TeamDr. Peter Wigand, Adam Herrera,

Katie Irwin, Robert Kelty, Joseph ScottSJVRocks!!

CSUBakersfieldDepartment of Geological Sciences

Background Power Point

Vocabulary BuilderLet’s core!!Lake Core ActivityPollen ActivityLet’s Put It All

Together!!

SJVRocks!! CSUBakersfield

Department of Geological Sciences

Paleoclimatology is the study of ancient regional and global climates.

This science is quite intriguing considering the fact that the means of measuring precipitation and temperature were not available.

Since it is not possible to go back in time to see what climates were like, how do scientists determine these past climates?

… or can we? SJVRocks!! CSUBakersfield

Department of Geological Sciences

Past climates can be reconstructed using a combination of different types of “imprints”, or proxies, created during past climate periods.

Proxies include tree rings, ice cores, fossils, pollen, ocean sediments, corals and historical data.

…How do we get the data? SJVRocks!! CSUBakersfield

Department of Geological Sciences

Climate refers to the average daily and seasonal weather conditions (such as air temperature, humidity, wind, and precipitation).

Seasonal climate prediction is the process of estimating the most probable condition of the average surface temperature and precipitation for the future.

Climate prediction is typically expressed as the departure from a long-term average, or so-called normal climate or the subsequent seasonal average of temperatures and precipitation that will be below, above, or near this normal climate state. SJVRocks!!

CSUBakersfieldDepartment of Geological Sciences

Tree-ring cores are taken by using an increment borer to screw into the side of a tree. The cores are sanded, so the surfaces are smooth and the annual tree growth rings can be clearly seen. These are then analyzed for patterns that can be first correlated to modern climate records and then extrapolated to reconstruct ancient climates.

By drilling into the earth with a hollow tube sediment is collected in intact cores. These provide an often continuous, undisturbed cross-section of the subsurface stratigraphy.

Because pollen grains are composed primarily of a natural plastic, they are often well preserved within each sediment layer collected from the bottom of ponds, lakes, oceans, or other stratified deposits. By analyzing the pollen types recovered, scientists can infer specific environmental conditions each thrived in based upon there modern climatic context.

SJVRocks!! CSUBakersfield

Department of Geological Sciences

Sediments are most often transported by either water (fluvial processes) or they are transported by wind (aeolian processes) and glaciers.

Beach sands and river channel deposits are examples of fluvial transport and deposition, though sediment also often settles out of slow-moving or standing water in lakes and oceans.

Desert sand dunes is an example of aeolian transport and deposition.Glacial moraine deposits and till are ice transported sediments.

The deposition rate of lake sediments is controlled by many factors. Lake morphology (area, depth, shoreline’s length), water circulation, climate conditions, area and land use in the catchment, are only some of these features. Some of them could be driven by human activity and thus rapid changes of sedimentation rate and historical events (e.g. settlement events, changes of predominant economy type, wars etc.) are often correlated. Sedimentation rate is also influenced by composition of plant and animal communities present in a lake.

SJVRocks!! CSUBakersfield

Department of Geological Sciences

http://serc.carleton.edu/microbelife/topics/proxies/paleoclimate.htmlhttp://www.humboldt.edu/~cga/calatlas/index.htmlhttp://web0.greatbasin.net/~wigand/petespaleo/http://www.phschool.com/ (Earth Science Textbook Prentice Hall)http://my.hrw.com/ (Holt McDougal Online)http://www.ncdc.noaa.gov/paleo/primer.htmlhttp://www.geo.arizona.edu/palynology/http://archaeology.about.com/od/seterms/qt/sediment_core.htmhttp://www.ncdc.noaa.gov/paleo/globalwarming/proxydata.htmlhttp://www.ace.mmu.ac.uk/resources/gcc/3-3.htmlDr. Peter Wigand University of Reno, Nevada Project ExpertDr. Staci Loewy CSUBakersfield, California Project Expert

SJVRocks!! CSUBakersfield

Department of Geological Sciences