
Vegetation patterns in mathematical models, and vegetation patterns in Horn of Africa
21 Apr 2016  Presentations
Visually striking largescale spatial patterns of vegetation have been observed in semiarid regions in the Americas, Africa and Australia. These have led to suggestions by theoretical ecologists that certain characteristics of the patterns may serve as earlywarning signs of desertification....

New averaging results motivated by climate models: fat tails, oscillations, and tipping
10 Dec 2015  Presentations
We review recent results where new averaging approaches are developed and applied in the context of systems with multiple time scales and fat tails and in nonautonomous multiple scale systems with oscillatory forcing. These types of systems appear in a variety of higher dimensional...

Tipping points and power cuts
18 Jun 2015  Presentations

Who, or what, will tip the big climate models?
18 Jun 2015  Presentations

ICMS Tipping Points: Fundamentals and Applications
13 Jun 2015  Workshops
Objectives: This workshop (September, 2013) brings together mathematicians and statisticians, whose research expertise is relevant to investigating threshold behaviour in complex environmental systems, with the climate scientists and ecologists who exploit mathematical modelling in their research...

Midwest Mathematics and Climate Conference  Day 2 Afternoon Session
12 May 2015  Presentations
Charles Jackson, University of Texas, AustinDualstate Behavior of the Community Climate System ModelIce age climate between 80,000 and 11,000 years ago experienced abrupt (< 10 year) globalscale climate transitions every few thousand years. Evidence and theory suggests such behavior may be...

Midwest Mathematics and Climate Conference
12 May 2015  Workshops
The conference is sponsored by the National Science Foundation, Institute of Mathematics and Its Applications, the Office of Research,College of Liberal Arts and Sciences, and the Department of Mathematics, Department of Geography/Atmospheric Science Program, and The...

Introduction to the Mathematics of Climate at UMN  Lecture 18
12 May 2015  Presentations
This is lecture 18 in the series "Introduction to the Mathematics of Climate" offered at the University of Minnesota in 2014 with the support of MCRN and The Institute for Mathematics and its Applications.

Introduction to the Mathematics of Climate at UMN  Lecture 14
12 May 2015  Presentations
This is lecture 14 in the series "Introduction to the Mathematics of Climate" offered at the University of Minnesota in 2014 with the support of MCRN and The Institute for Mathematics and its Applications.

Realistic modeling and analysis of synchronization dynamics in powergrid networks
08 May 2015  Presentations  Contributor(s): Mary Lou Zeeman
An imperative condition for the functioning of a powergrid network is that its power generators remain synchronized. Disturbances can prompt desynchronization, which is a process that has been involved in large power outages. In this talk I will first give a comparative review of three leading...

Introduction to the Mathematics of Climate
07 May 2015  Series
This course will investigate the following questions from a mathematical perspective. What determines the Earth's surface temperature? Why does the carbon dioxide in the atmosphere affect the climate? How do changes in the Earth's orbital parameters change the climate? Why has the Earth...

Synchronization in power grid networks
07 May 2015  Presentations  Contributor(s): Mary Lou Zeeman
This survey discusses Master Stability Function (MSF) analysis for determining stability of synchronization of coupled oscillators on network. In addition, we briefly discuss the derivation of the Swing equation that determine the dynamics of a node in power grid network, and...

Complex Energy Systems
07 May 2015  Presentations  Contributor(s): Mary Lou Zeeman
This is the opening guest lecture for the Electric Grid Focus Group. Dr. Michael Chertkov of Los Alamos National Lab describes the statistical and mathematical problems arising in complex energy systems, including the electric grid and gas networks. Systems with high penetration of...

A Survey of Grid Control and Optimization
07 May 2015  Presentations  Contributor(s): Mary Lou Zeeman
This is an introductory survey of how control problems arise on different time scales in electric grid transmission problems. The set up and general form of such problems are considered, along with operational considerations.

Particle filters for geophysical applications
30 Apr 2015  Presentations  Contributor(s): Mary Lou Zeeman
Avoiding degeneracy is a crucial challenge for particle filters. Results have shown that the number of particles scales exponentially with respect to the number of independent observations. In this talk I will review attempts to counteract this phenomenon by exploiting proposal densities. I will...

Toward a hybrid particleensemble Kalman filter for assimilating data from Lagrangian instruments into high dimensional models
30 Apr 2015  Presentations  Contributor(s): Mary Lou Zeeman
Presented by Elaine Spiller on 32615Abstract:We discuss a recently proposed hybrid particleensemble Kalman filter for assimilating Lagrangian data, and apply it to a highdimensional quasigeostrophic ocean model. Effectively the hybrid filter applies a particle filter to the highly nonlinear,...

Emulators in climate science. Uncertainty, sensitivity, calibration and more
30 Apr 2015  Presentations  Contributor(s): Mary Lou Zeeman
An emulator or a surrogate is a statistical approximation of a complex numerical model. Emulators are fast to run and include a measure of their own uncertainty. This makes them suitable for a number of applications in climate science. Emulators were originally devised for uncertainty...

Statistical Data Assimilation For Parameter Estimation In Costal Ocean Hydrodynamics Modeling
30 Apr 2015  Presentations  Contributor(s): Mary Lou Zeeman
Coastal ocean models are used for a variety of applications, including modeling tides and hurricane storm surge. These models numerically solve the shallow water equations, which are derived by depth integrating the NavierStokes equations. The inherent uncertainties in coastal ocean models are a...

Correlated Observation Errors in Data Assimilation
30 Apr 2015  Presentations  Contributor(s): Mary Lou Zeeman
Remote sensing observations often have correlated errors, but the correlations are typically ignored in data assimilation for numerical weather prediction. The assumption of zero correlations is often used with data thinning methods, resulting in a loss of information, and reduction in analysis...

An Introduction to Lagrangian Data Assimilation  Part II
23 Mar 2015  Presentations  Contributor(s): Mary Lou Zeeman
Lauara Slivinski at Woods Hole Oceanographic Institution gives an introduction to Lagrangian Data Assimilation on 11132014.