Lab 2 Part A

Go to the class webpage and choose ‘Links’, then ‘VERY COOL LAB ACTIVITIES’.  Click on Lab Activity #7, “Vertical Profiles of Temperature and Salinity in the Ocean”. 

 

Follow the link provided http://www.pmel.noaa.gov

 

Click on the ‘Data’ pulldown menu and choose ‘NOAA Ship KA’IMIMOANA’

 

Click on ‘Research’, then ‘CTD Data’.

 

Most of these data were collected by the NOAA research ship Ka'imimoana, which was designed and is dedicated to maintaining an array of buoys in the tropical Pacific Ocean to help monitor the development of El Niño and La Niña events, which are phenomena of the surface and near-surface Pacific Ocean. The buoys were deployed as part of the Tropical Atmosphere-Ocean (TAO) Project. The Ka'imimoana (and another ship occasionally serving the same purpose, the Ron Brown) also records "soundings" of temperature and salinity, called CTD data, down to a depth of about 500 meters. The data provided by NOAA consists of meridional contour plots (vertical slices along lines of longitude, in this case across the equator between +/-8° latitude).

    (1) In the first column of the data selection array, select "GP4-99-KA", which, shows a map of the two meridional transects along which the ship collected data in August, 1999. As you can tell from the data array, the temperature and salinity data were collected along 165°E and 180°W longitudes.

        (a) In what part of the equatorial Pacific Ocean (east, central, or west) were these data collected?

        (b) Examine the temperature and salinity data along 165°E. What are the main features of each and how deep are they, or what is the range of depths at which you see them? Do temperature and salinity profiles have the same structure? Pose hypotheses that might account for the main features of each, if possible based on information provided in assigned reading.

        (c) Are there differences between Northern and Southern Hemispheres? Pose a hypothesis about what might account for the differences, based if possible on information provided previously in class or in assigned reading.

    (2) Repeat (1) (a)-(c) for the September 1996 transect along 125°W and the October 2000 transect along 110°W. What differences do you see, if any, between the different parts of the equatorial Pacific Ocean? Pose a hypothesis that might account for the differences, based if possible on information provided in previously class or in assigned reading.

 

 

 

Climate Change Lab #2b

GEO 302C

 


 

Situation
It is the summer of 1997, and a new El Niño is beginning. Early indications are that this El Niño will rival the 1982-83 El Niño, the most intense of the century. In Australia, drought advisories have been issued. During the 1982-83 El Niño, rainfall throughout most of the wetter parts of Australia were in the lowest 20th percentile, with many other areas in the lowest 10th percentile. In parts of Peru, 11 feet of rain fell where 6 inches had been the norm. Throughout the world, numerous other anomalous weather events occurred: drought in Brazil, heavy snow in Texas, floods in Europe, and a monsoon failure in India. The biosphere was also affected as crops and fisheries failed.

Already, the Southern Oscillation Index (SOI) is showing monthly magnitudes greater than -24. Daily values reached as high as -85 in June 1997. The latest SOI values are here. During the 1982-83 El Niño, monthly values peaked at -35.7. SOI data since 1900 are available. By June 1997, water temperatures in parts of the eastern Pacific were more than 4°C higher than normal, the warmest temperatures recorded in that area since August, 1983.

This departure from normal temperature is called an "anomaly." As you proceed further into your investigation of the El Niño problem, you will see that much of the data is presented in terms of anomalies. This presentation tends to be more useful than the actual data, since the developing conditions are distinguished from the normal. (Information on how anomalies are computed for sea surface temperatures is included here.)

As the new El Niño develops, an anomaly is also taking place in the winds. For only the second time since November 1982, westerly trade winds replaced easterlies in the Pacific from 160E to 100W longitude.

If the wind has an easterly component, it is shown as a negative on the chart above. A westerly component (anomalous situation) is depicted as a positive value. The value of 850 hPa indicates theses winds were measured at an atmospheric pressure of 850 millibars, about 5000 feet above the sea's surface.

Convection had decreased in the western Pacific but increased near the dateline.

Faced with a rapidly changing situation, the director of the World Bank and the president of the Northern Insurance Negotiating Organization (Nino) have approached your group of environmental consultants for advice in forecasting the environmental conditions and economic impact that will accompany this developing El Niño. They want to know not only what can be expected from this El Niño with regard to weather, fisheries, and crops, but also how its impact can be softened.

El Nino Reference Page: http://davem2.cotf.edu/ete/modules/elnino/elnino.html

                                     http://www.pmel.noaa.gov/tao/elnino/nino-home.html

El Nino Lab Page: http://davem2.cotf.edu/ete/modules/elnino/crsituation.html

 

 

 

El Nino:  Supplemental Questions for Study      

GEO 302C                                             Name:__________________

                                                                              

                                       

Related Links (if needed):

http://www.pmel.noaa.gov/tao/elnino/faq.html

 

http://topex-www.jpl.nasa.gov/science/enso97/el_nino_1997.html

http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/eln/home.rxml

 

http://davem2.cotf.edu/ete/modules/elnino/crsituation.html

 

 

1.What is El Nino and how does it affect the normal pattern of oceanic circulation in the Pacific Ocean? What is La Nina, and how does it affect the normal pattern of oceanic circulation in the Pacific Ocean?

 

 

 

 

 

 

 

 

 

 

2.When was the most recent notable El Nino event? How long did     

 it last? What longer term phenomenon is currently dominant in                                   the Pacific Ocean’s circulation patterns? Hint- go to website:

http://topex-www.jpl.nasa.gov/science/enso97/el_nino_1997.html

 

 

 

 

 

 

 

 

 

 

 

3. Scientists installed a series of buoys in the Pacific Ocean to measure the extent of El Nino. What factors do scientists measure to identify El Nino? How have these factors differed from normal conditions?

 

 

 

 

 

 

 

 

 

 

4.Draw the maximum geographic extent of El Nino on the map below:

 

 

 

 

5.    El Nino is often linked to upwelling of cold ocean waters. Where does this upwelling occur and what impact does El Nino have on it?

 

 

 

 

 

 

 

 

 

 

 

 

6. How has the El Nino Event affected weather patterns in a) Australia and Indonesia, and, b) North America?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The majority of this Lab Exercise was written by Dr. David McConnell, Associate Professor of Geology at the University of Akron, Akron, Ohio, 1998.