Publications


Niederfrequente Variabilität großräumiger atmosphärischer Zirkulationsstrukturen in spektralen Modellen niederer Ordnung. Reports on Polar Research.

AWI (2000) 356

A Weisheimer


Seasonal skill and predictability of ECMWF PROVOST ensembles

QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY 126 (2000) 2035-2067

C Brankovic, TN Palmer


3D-Var Hessian singular vectors and their potential use in the ECMWF Ensemble Prediction System

QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY 125 (1999) 2333-2351

J Barkmeijer, R Buizza, TN Palmer


A nonlinear dynamical perspective on climate prediction

JOURNAL OF CLIMATE 12 (1999) 575-591

TN Palmer


The effect of land-surface feedbacks on the monsoon circulation

QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY 125 (1999) 1527-1550

L Ferranti, JM Slingo, TN Palmer, BJ Hoskins


Stochastic representation of model uncertainties in the ECMWF Ensemble Prediction System

QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY 125 (1999) 2887-2908

R Buizza, M Miller, TN Palmer


Analysis and model dependencies in medium-range ensembles: Two transplant case-studies

QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY 125 (1999) 2487-2515

MSJ Harrison, TN Palmer, DS Richardson, R Buizza


Signature of recent climate change in frequencies of natural atmospheric circulation regimes

NATURE 398 (1999) 799-802

S Corti, F Molteni, TN Palmer


Impact of ensemble size on ensemble prediction

MONTHLY WEATHER REVIEW 126 (1998) 2503-2518

R Buizza, TN Palmer


Monsoons: Processes, predictability, and the prospects for prediction

JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS 103 (1998) 14451-14510

PJ Webster, VO Magana, TN Palmer, J Shukla, RA Tomas, M Yanai, T Yasunari


A nonlinear dynamical perspective on climate predictability: Rossby's legacy

NINTH SYMPOSIUM ON GLOBAL CHANGE STUDIES (1998) 351-351

TN Palmer, AM SOC, AM SOC


Sensitivity analysis of forecast errors and the construction of optimal perturbations using singular vectors

JOURNAL OF THE ATMOSPHERIC SCIENCES 55 (1998) 1012-1037

R Gelaro, R Buizza, TN Palmer, E Klinker


Impact of model resolution and ensemble size on the performance of an Ensemble Prediction System

QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY 124 (1998) 1935-1960

R Buizza, T Petroliagis, T Palmer, J Barkmeijer, M Hamrud, A Hollingsworth, A Simmons, N Wedi


Decaying singular vectors and their impact on analysis and forecast correction

JOURNAL OF THE ATMOSPHERIC SCIENCES 55 (1998) 3005-3023

CA Reynolds, TN Palmer


Nonlinear dynamics and climate change: Rossby's legacy

BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY 79 (1998) 1411-1423

TN Palmer


Singular vectors, metrics, and adaptive observations

JOURNAL OF THE ATMOSPHERIC SCIENCES 55 (1998) 633-653

TN Palmer, R Gelaro, J Barkmeijer, R Buizza


Atmospheric seasonal predictability and estimates of ensemble size

MONTHLY WEATHER REVIEW 125 (1997) 859-874

C Brankovic, TN Palmer


A study of the predictability of tropical pacific SST in a coupled atmosphere-ocean model using singular vector analysis: The role of the annual cycle and the ENSO cycle

Monthly Weather Review 125 (1997) 831-845

YQ Chen, DS Battisti, DS Battisti, TN Palmer, J Barsugli, ES Sarachik

The authors examine the sensitivity of the Battisti coupled atmosphere-ocean model - considered as a forecast model for the E1 Niño-Southern Oscillation (ENSO) - to perturbations in the sea surface temperature (SST) field applied at the beginning of a model integration. The spatial structures of the fastest growing SST perturbations are determined by singular vector analysis of an approximation to the propagator for the linearized system. Perturbation growth about the following four reference trajectories is considered: (i) the annual cycle, (ii) a freely evolving model ENSO cycle with an annual cycle in the basic state, (iii) the annual mean basic state, and (iv) a freely evolving model ENSO cycle with an annual mean basic state. Singular vectors with optimal growth over periods of 3, 6, and 9 months are computed. The magnitude of maximum perturbation growth is highly dependent on both the phase of the seasonal cycle and the phase of the ENSO cycle at which the perturbation is applied and on the duration over which perturbations are allowed to evolve. However, the spatial structure of the optimal perturbation is remarkably insensitive to these factors. The structure of the optimal perturbation consists of an east-west dipole spanning the entire tropical Pacific basin superimposed on a north-south dipole in the eastern tropical Pacific. A simple physical interpretation for the optimal pattern is provided. In most cases investigated, there is only one structure that exhibits growth. Maximum perturbation growth takes place for integrations that include the period June-August, and the minimum growth for integrations that include the period January-April. Maxima in potential growth also occur for forecasts of ENSO onset and decay, while minima occur for forecasts initialized during the beginning of a warm event, after the transition from a warm to a cold event, and continuing through the cold event. The physical processes responsible for the large variation in the amplitude of the optimal perturbation growth are identified. The implications of these results for the predictability of short-term climate in the tropical Pacific are discussed.


The past and the future of El Nino

NATURE 390 (1997) 562-564

PJ Webster, TN Palmer


The impact of increased resolution on predictability studies with singular vectors

QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY 123 (1997) 1007-1033

R Buizza, R Gelaro, F Molteni, TN Palmer