GEOS 597e: Spatiotemporal Data
Analysis Workshop
Homework 9: Independent projects
Last updated
10/27/06.
Oral
presentations to be completed
by 12pm, Weds., Nov. 29th.
Goals of this assignment
- Apply the empirical analysis tools you have built during our
study of the GOSTA SST anomaly dataset to a different climate dataset
of
your choice.
- Analyze, interpret, and critically evaluate the results.
- Provide constructive peer review of scientific results;
effectively incorporate constructive criticism on your work via peer
evaluation.
- Improve your oral communication skills by presenting
your results in short oral format.
Introduction
At this point in the semester, we have developed tools for performing
empirical orthogonal function analysis of three dimensional
datasets, and for singular spectrum analysis of time series, using a
high-level scripting programming language. We have also developed
tools and intuition for the estimation of error and uncertainty in the
products of these analyses. We have used these tools to (hopefully)
wisely filter and interpret the resulting patterns, and we have honed
those analytical skills by examining examples in the scientific
literature of similar analyses.
In this assignment I ask you to now use the tools and skills you have
developed to analyze and interpret the large-scale features in a three
dimensional meteorological or climatic dataset of your choice.
Use the structure of previous Prework, Preview, and Homework
assignments
to develop, execute, and illustrate the results of your analysis. I
expect to see your project to cover at least the following topics;
however, you are encouraged to probe more deeply into the data to
produce a nuanced, thoughtful spatiotemporal analysis.
- EOF decomposition of your spatiotemporal dataset.
- Analysis: Truncate and filter the data; test the results for
error and stability using Monte Carlo techniques.
- Perform varimax rotation of the leading subset of EOF patterns
and assess interpretability of the results relative to unrotated EOFs.
- Use the results of the EOF analysis to choose a representative
index time series from the spatiotemporal dataset.
- Perform SSA decomposition of your time series dataset.
- Analysis: Truncate and filter the data; test the results for
error and stability using Monte Carlo techniques.
- Interpret the results: what are the leading patterns of spatial
and temporal variation in the data set? Could they be plausibly
the result of physical mechanisms of climate variation; and if so, how?
Products
You will report your findings as a 15
minute oral presentation. Some suggestions for developing
an
effective oral presentation:
- Start with the larger goal of the work. Why is it
important? Fundamental climatological science question?
Societal relevance? Other? What are the implications
of discovering the answer?
- Give a brief, but clear and concise statement of the specific
research question which motivated your choice of dataset to analyze.
Sometimes this is best expressed in question form. What did
you expect to see result from this analysis, based on prior knowledge
of
the climate system or of the underlying physical climatology?
- Lay out the essential components of your experimental strategy
so we can see where you're going. In a short presentation, good
organization will help you make even a subtle argument clear in a short
amount of time.
- Take some time to really dissect the figures you show us --
they are usually central to a scientific argument. Choose your figures
carefully, and use them to illustrate your discussion points.
Explain your figures to the class as if you are explaining things
to a non-expert. What are the axes and units? What is plotted? What
points are made by presenting the figure? Guide us through your
interpretation of the figure.
- Take some time to discuss the major assumptions or
uncertainties in the approach you have described. You might
anticipate, and answer, expected questions about your approach.
- Finish with a slide describing the major outcomes. How can
the results be applied to resolving the scientific question which
motivated the work in the first place?
- Put enough text and description on your slides to remind
yourself to hit the major points and to note important details, but not
so much that you are tempted to read from your slides. Instead,
tell us the story of what you found from your analyses. Note that
giving a talk doesn't necessarily follow the same structure of a
written report.
- Practice your presentation to yourself or to a
classmate/friend. Just running through it once out loud will help
you work out timing and bugs, to fill in logical gaps, and make clearer
slides. A second rehearsal will often shock you by how much more
smoothly it goes.
- All slides containing results or ideas taken from the literature
should include citations, and your presentation should include a final
slide of Cited References (your presentation of your project need not
include reading us the reference list, of course). For instance,
the source of your analyzed data set should be given (e.g. Woodruff et al.,
1998) and the
Cited References slide should include the reference
Woodruff,
S.D., Diaz, H.F., Elms, J.D., Worley, S.J., 1998. COADS Release 2 data
and Metadata Enhancements for Improvements of Marine Surface Flux
Fields. Phys.
Chem. Earth 23, 517-526,
accessed via Internet, 1 May 2003:
http://www.cdc.noaa.gov/coads/egs_paper.html.
Schedule
You are free to make best use of your time over
the next month to complete this assignment. However, if you'd
like
some guidelines to structure your time, here is a roadmap for this
assignment.
Week 1 (Nov
1st-Nov 7th): Choose your target dataset and plan your
experiment. Please see Mike for a 10 minute conference during
class this week, for help with and/or approval of your chosen project.
Use the answers to these questions to develop the introduction to your
project report and presentation.
- Target dataset:
- What scientific question would you like to ask using the
observed variable?
- What is the source of the dataset, including published
references on its development?
- What are the major uncertainties in the raw data?
- How was this specific dataset produced? What were the
major processing steps?
- What are the major potential uncertainties in the resulting
product?
- Plan your experiment:
- How will you apply EOF and SSA analysis to this dataset?
Use the structure of the course and what you have learned from
Preworks and Homeworks 1-8.
- What is your a priori
expectation for the results, given your understanding of the underlying
climate system?
- What tests will you apply to determine the robustness of your
results?
- Logistics:
- Find a source for your data. Most likely it will be from
an online data repository of digitized data.
- Be sure to document the source of your data, including both
internet and peer-reviewed references.
- Be sure to download the data in a form which both you and
Matlab can understand and read. Some good sources of data are the
LDEO/Ingrid Data Catalog;
JISAO's Climate
Data Archive; KNMI Climate
Explorer. Best standard formats for large datasets are binary
random access, netcdf,dods. I can help you directly
if you get your data from Ingrid; if you have netcdf and/or dods
sources, tools here and here are available
to help you read these files directly into matlab (ask me or Eneida
about getting these on clue machines asap). Bottom
line: take the easiest route to getting the data you can possibly find;
this is a minor component of the project.
Week 2 (Nov. 8th-Nov. 14th): Decompose and analyze your
dataset. Use your results to develop and illustrate your written
project report and your oral presentation. Digest your
findings: this is easily the most
important component of your project. Be sure to allow adequate
time to probe and really study the results that you find.
- Execute your experiment.
- Perform EOF decomposition of your spatiotemporal dataset.
- Analysis: Truncate and filter the data; test the results for
error and stability using Monte Carlo techniques; if pertinent, perform
rotation of selected EOF patterns and examine differences
between rotated and unrotated EOFs, and improvements (or not) in
interpretative value.
- Use the results of the EOF analysis to choose a representative
index time series from the spatiotemporal dataset.
- Perform SSA decomposition of your time series dataset.
- Analysis: Truncate and filter the data; test the results for
error and stability using Monte Carlo techniques.
- Analysis: perform any other calculations or analyses to support
or illustrate your results.
- Analyze the results.
- How many significant patterns are there? How much of the
variance do they represent?
- Are there plausible physical interpretations for any of the
leading
patterns?
- How would you use the results to filter the dataset?
- How robust are your results and interpretation, considering
observational error, analysis uncertainity, and ability to resolve
patterns?
- Digest the results.
- What are your primary findings (results and interpretation)?
- How do your results compare to results or interpretations in
the scientific literature?
- How have you addressed the motivating scientific question you
posed at the outset?
- Did you find anything particularly interesting or surprising
given your a priori
expectations?
Week 3 (Nov. 15th-21st): Develop an oral presentation
describing your analysis of the dataset.
- Starting with items from part (3) from Week 2, construct a clear,
well-illustrated oral and visual presentation of your motivating
scientific question and primary findings. See Products
above for some suggestions on how to develop an effective oral
scientific presentation.
Week 4 (Nov. 22nd - Nov 28th):
Have a nice Thanksgiving Break.
Week 5 (Nov. 29th - Dec 5th):
Project presentations
- Oral presentations, to be made in class, Wednesday, Nov 29th; class to be held at Tree-Ring Lab West,
Seminar Rm. 20, Mathematics East Building.
- Important: please email your Powerpoint presentation to Mike no later than 12pm, Wednesday Nov 29th. Name your presentation lastname.ppt.
I will load these all onto a classroom (windows) computer in time for
class, and I will review them for grading. If you cannot or do
not
wish to use Powerpoint, please talk to Mike well ahead of time about
alternative
arrangements; if you work outside of windows, you may wish to test your
presentation on a windows box before class. Each talk slot will
be 15 minutes: 10 minutes to present, 4 minutes for questions, and 1
minute for
evaluation and changeover to the next speaker.
- See the grading rubric for my
expectations for this project.
- Submit completed peer reviews (see below).
Evaluation
- Be sure to review the grading rubric before beginning the
assignment, so you understand my expectations for this assignment.
- We will use the peer evaluation form
to evaluate the presentations (I'll bring 8 x 8 copies to class).
- 50% of your grade will be determined by your classmates'
evaluations of your presentation; 50% by MNE. Together this will
be 41% of your course grade.
- I will submit final grades to Anne Chase and
distribute grades to each of you by email by end of week of Dec 11th .
- Please be sure to pick up
any other graded materials of yours I may still have at my office in
the W. Stadium, or give me a campus address to which I can send them.
Back
to Schedule/Syllabus.