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Geostatistical Project, NCAR and Department of
Statistics, CSU Mini Seminar Series
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A
Spatial Model for Precipitation Occurrence, Sarah Streett
Monday, 17 November 2003
3:10PM - 3:35 PM
232 Wagar
ABSTRACT
Stochastic weather generators
play an important role in the assessment of climate on agriculture. Of particular importance is the
model used for precipitation occurrence since the remaining weather
variables are often modeled conditionally based on this event. An observation driven model for
occurrence is introduced and results depicting the model's capability of
generating realistic precipitation patterns are shown. Spatial extensions of the model are
also discussed.
Optimal Interporation (OI) Analysis of High-latitude Ionospheric
Electrodynamic Variables, Tomoko Matsuo
Monday, 17 November 2003
3:35PM – 4:00 PM
232 Wagar
ABSTRACT
The Assimilative Mapping of
Ionospheric Electrodynamics (AMIE) procedure, developed by Richmond and
Kamide [1988], carries out an objective multivariate functional analysis of
high-latitude ionospheric electrodynamic variables: electric fields,
electric potential, ionospheric currents, and magnetic field perturbations. In this talk some technical
improvements upon the traditional implementation of the OI method are
demonstrated for the storm period of January 9-11, 1997. Improvements include the use of the
set of 11 Empirical Orthogonal Functions (EOFs) of Matsuo et al. [2002] as
basis functions, and also the application of of the maximum-likelihood
method [Dee, 1995] for the error covariance parameter estimation.
BREAK:
4:00pm – 4:10pm
Extreme Value Theory in (Hourly) Precipitation, Uli
Schneider
Monday, 17 November 2003
4:10pm – 4:35pm
232 Wagar
ABSTRACT
This project revolves around
studying precipitation extremes.
One of the goals is to assess the impact of hourly precipitation
extremes to flood hazards, another long term goal will be to make inference
from large scale climate model output to precipitation extremes happening
on a more local level. As a
starting point we apply tools from extreme value theory to several rain
gage stations in the Colorado Front Range with the intent of improving
precipitation atlas used to determine flood hazards.
Off-line Transport Models and The Carbon Cycle, Reinhard
Furrer
Monday, 17 November 2003
4:35pm – 5:00pm
232 Wagar
ABSTRACT
To understand the present and future climate it is
indispensable to have a precise description of the carbon cycle, aerosols,
particle matter etc. The carbon cycle itself depends strongly on anthropogenic activities such as the
change of land-use and emissions from fossil fuels and cement production
(sources of carbon). On the other hand the carbon is up-taken via the ocean
and respiration of green matter (sinks). It is impossible to quantify
precisely large scale sinks and sources of carbon; but they can be
estimated indirectly through carbon concentration measurements, defining an
inverse problem. This project focuses on the statistical issues related to
this inverse problem. The central motor of an inverse problem is a forward
operator, more specifically, an off-line transport model. In this short talk I will
illustrate the basics of transport models with respect to the carbon cycle.
Several statistical questions and problems in the context of the carbon
cycle will be outlined
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