Increasing the Interoperability of an Earth System Model:

Atmospheric-Ocean Dynamics and Tracer Transports

NCC4-624

Milestone D

Final Report: 1- 30 May 2006

 

1.              Objective

This CAN addressed three major thrusts of the ESS Project: 1) to further our understanding of and ability to predict the dynamic interaction of physical and chemical processes affecting Earth, 2) to incorporate the use of NASA data, and 3) to demonstrate interoperability of codes used in the community of Earth Science.

We acted as early adaptors of the Earth System Modeling Framework (ESMF).  Our role consisted of integrating into this framework the UCLA Earth System Model (ESM) gridded components: 1) atmospheric general circulation model (AGCM) developed at UCLA,  2) oceanic GCM (OGCM) known as Parallel Ocean Program (POP) and 3) OGCM developed at the Massachusetts Institute of Technology (MIT). The ESMF functionality was demonstrated by analyzing the El Ni–o prediction capability of the AGCM coupled to the POP and MIT OGCM, in combination with NASA/JPL ocean data and optimization products.

2.         Approach

We followed a three-tiered approach.

Tier I consisted of integrating the coupled atmosphere-ocean part of the UCLA (ESM) into the ESMF. The model and its components are described in Milestone A.

Tier II addressed the issues of code interoperability by using the ESMF services to couple the AGCM with either POP or the OGCM developed at the (MIT), and by performing forecasts of El Ni–o/Southern Oscillation (ENSO).

Tier III focused on the impact of NASA data and consisted of comparing ENSO forecasts made from initial conditions corresponding to the quasi-operational analysis of the time-evolving ocean circulation produced by the consortium for Estimating the Circulation and Climate of the Ocean (ECCO) maintained at the Jet Propulsion Laboratory (JPL). The ECCO product is updated approximately once per week, is freely available (http://ecco.jpl.nasa.gov).  The MIT OGCM is a component in ECCOÕs data assimilation system, while POP is not.

3.         Scientific Accomplishments

The parameterization of planetary boundary layer (PBL) processes used in the UCLA AGCM was upgraded. The upgrade improved the simulations in several respects, particularly in the surface fluxes that play key roles in the coupling between atmosphere and ocean (Milestone F).

We use the UCLA AGCM coupled with the MIT global OGCM in order to obtain ensemble seasonal hindcasts for the years 1993-2001, which include strong El Ni–o and La Ni–a events. We consider two kinds of initial conditions for the OGCM: a) estimates provided by the JPL's Estimating the Circulation and Climate of the Ocean (ECCO) project, and b) fields obtained from a long uncoupled OGCM simulation (with prescribed SST and wind stress from observations) for a period that includes 1993-2001 (ECCO and baseline initial conditions respectively). The hindcasts start from either early March or early June and extend for fifteen months. We found that forecast skill is relatively high in all cases, with higher values for initial conditions in June. Forecast skill is much higher than persistence in the March cases (see Fig. 1). Our results show that initial ocean states can have a significant influence on the skill of seasonal forecasts with a coupled atmosphere-ocean CGM. ECCO initial conditions have smaller, perhaps more realistic, anomalies than the baseline initial conditions. This might be associated with a more realistic climatological thermocline in the ECCO set.

4.         Technology Accomplishments (including progress toward milestones)

The Distributed Data Broker (DDB) developed under Round 2 of this CAN project was upgrade and further developed.  This included support for MPI and shared memory, improve performance, improve diagnostic and error handling, improve user interface and deliver updated documentation for the Distributed Data Broker (Milestone I).

The OGCM POP was upgraded to a near global domain (excluding both polar regions) without loss of performance compared to E (Milestone G).

The ESMF services were used to couple the UCLA AGCM and POP, and integrate them into the ESMF framework (Milestone J). Extensive work was performed with the UCLA AGCM itself to make it ESMF compliant. The modelÕs own control code and coupling routines were removed. To conform to ESMF methodology, entry points were defined in the model to allow for discrete calls to the initialize, run, and finalize methods. No functional or performance degradation was found. The code can still run stand-alone (without ESMF) by setting a flag. Chris Hill and Phil Jones modified the MIT OGCM and POP, respectively, to be ESMF compliant.

The ESMF functionality was demonstrated by analyzing the El Ni–o prediction capability of the UCLA AGCM coupled to POP and the MIT OGCM, in combination with NASA/JPL ocean data and optimization products.


5.         Point of contact (name, address, email)

Carlos R. Mechoso, Professor

University of California, Los Angeles

Department of Atmospheric Sciences

7127 Math Sciences Building

405 Hilgard Avenue

Los Angeles, California 90095-1565

Phone:  310-825-3057

FAX:    310-206-5219

Email: Mechoso@atmos.ucla.edu

www.atmos.ucla.edu/~mechoso

 

 

 

 

 

 


6.         Caption for the graphic




 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


For forecasts initiated in March, those obtained using initial conditions from the JPL/ECCO project show smaller root mean square errors in the equatorial Pacific than the forecasts from initial conditions from the model fields without data assimilation and the persistence forecasts.

 

7.         List (and abstracts) of all publications which cite work performed under this CAN

Konor, C. S., Cazes-Boezio, G., A. Arakawa, and C. R. Mechoso, 2007: A Multi-Layer Bulk PBL Parameterization for Use in Climate Models: Application to an Atmospheric General Circulation Model. In preparation.

Cazes-Boezio, G., D. Menemenlis, and C. R. Mechoso, 2007: Impact of ECCO Ocean State Estimates on the Initialization of Seasonal Climate Forecasts. In preparation.

Cazes-Boezio, G., D. Menemenlis, and C. R. Mechoso. Experimental ENSO predictions by the UCLA atmospheric GCM coupled to the MIT and POP Oceanic GCMs using the Earth System Modeling Framework (ESMF).  In preparation.

8.         List of conference presentations resulting from work performed under this CAN

Mechoso, C. R.: The UCLA Earth System Model.  Second Annual Conference of NASA Office of Earth Science and Earth Science Technology Office (ESTO). 11-13 June 2002, Pasadena, California

Earth system modeling at UCLA. Computers in Atmospheric Sciences 2003 (CAS2K3), 8-11 September 2003, Annecy, France.

Mechoso, C. R., J. A. Spahr, C. Hill, P. Jones and D. Menemenlis: Integration of Atmosphere and Ocean General Circulation Models into the Earth System Modeling Framework . General Assembly of the European Geosciences Union, 24-29 April 2005, Vienna, Austria.

Cazes-Boezio, G., C. S. Konor, C. R. Mechoso, D. Menemenlis, and A. Arakawa:  Coupled Simulations Obtained with the UCLA AGCM with a New PBL Parameterization and the MIT Global OGCM.  AMS 17th Conference on Climate Variability and Change, 13-17 June 2005 Cambridge, Massachusetts.

(see http://ams.confex.com/ams/Cambridge/techprogram/ programexpanded_281.htm)

Mechoso, C. R.: Integration of a Coupled Atmosphere-Ocean Model into the ESMF (Earth System Model Framework). Computers in Atmospheric Sciences 2005 (CAS2K5), 11-14 September 2005, Annecy, France.

DeLuca, C., V. Balaji, A. da Silva, R.  Dunlap, Hill, C., Mark, L., C. R. Mechoso, D. Middleton, S. Nikonov, S. Rugaber, and M. Suarez: The Earth System Modeling Framework and Earth System Curator: Software Components as Building Blocks of Community. Presented by C. DeLuca at the 2006 Joint Assembly of the American Geophysical Society, 23-26 May 2006, Baltimore, Maryland.  See also Eos Trans. AGU, 87(36), Jt. Assem. Suppl., Abstract IN33A-03Eos Trans. AGU, 87(36), Jt. Assem. Suppl., Abstract IN33A-03

9.         Lists of all other media references in which the research was discussed.

The project was highlighted in the Summer 2005 issue of NASA CISTO News.

10.       List of any patents filed or new technology reports resulting from work under this cooperative agreement.

No patents resulted from work under this CAN

11.           List of graduate students or post docs trained; list of advanced degrees awarded and thesis titles (if available).

Cabriel Cazes-Boezio (Research Scientist)

Ingo Richter, PhD 2005

Heng Xiao, Advanced to PhD candidacy, January 2006.