CSL Allocations 2015

These projects received CSL allocations for June 2015 – May 2016

High resolution “next generation” CESM simulations with scale-insensitive physics

Project lead: Vincent Larson, University of Wisconsin – Milwaukee
Yellowstone allocation: 20.3 million core-hours
Sponsor: NSF

We propose to advance the practice of high-resolution climate simulation by treating sub-grid scale clouds with a unified cloud macrophysical parameterization that is applicable across grid scales. This multiscale cloud parameterization will be evaluated by performing a number of high-resolution simulations. The PI (Larson) possesses an NSF award that supports a Climate Process Team (CPT). The CPT has implemented a novel cloud parameterization, Cloud Layers Unified By Binormals (CLUBB, Larson et al. 2012), in the Community Earth System Model (CESM, Neale et al., 2010). Our primary overarching objectives are 1) to perform the high-resolution testing necessary to enable CLUBB to be accepted by the community as the default cloud parameterization in CESM2, 2) to perform some useful community simulations that can be used to evaluate the performance of the new model in present day, and 3) to get some idea of how the climate statistics may change in the future.

Dynamical Intraseasonal to Seasonal Prediction and Predictability

Project lead: Ben Cash, GMU/COLA
Yellowstone allocation: 19.9 million core-hours
Sponsor: NSF

To assess the impact of the twin issues of systematic and initial condition error on seasonal forecasting we will perform a suite of experiments using a state-of-the-art coupled climate model: the NCAR Community Earth System Model (CESM). We will first perform six-month hindcasts of 10 ensemble members each, initialized on the first of each month to fully sample the annual cycle, using four different ocean data products: ORA-S4, CFSR, and ECDA (see Section C). Runs will be performed for the full period covered by each product: 1979-2014 for CFSR and ECDA, and 1959-2014 for ORA-S4 and COMBINE-NEMOVAR. The ability to extend our hindcast set back to 1959 with the ORA-S4 and COMBINE-NEMOVAR data is particularly enticing, as it will significantly increase the total number of ENSO events considered. We will then perform an additional set of experiments in which the systematic bias in both the ocean mean state and the variability in the critical tropical eastern Pacific is corrected through the use of the pacemaker methodology.

Water isotope-enabled Transient Climate Evolution of the last 21,000 years (wiso-TRACE) — Understanding Deglacial Climate/Isotope Changes using wiso-CESM

Project lead: Zhengyu Liu, University of Wisconsin – Madison
Yellowstone allocation: 17.8 million core-hours
Sponsor: NSF

The overall goal of this project is to investigate the mechanisms of climate changes during the last deglaciation using water isotope enabled Community Earth System Model (wiso-CESM) and proxy records of the isotopic fingerprint of climate-change processes. The transient climate/isotope simulations allow, for the first time, the study of the continuous evolution and abrupt changes of climate from interannual to orbital time scales during the last deglaciation in a state-of-art isotope-enabled ESM under realistic forcing. The transient simulation of water isotopes marks a transformative breakthrough in model-data comparison, allowing for direct paleodata-tracer time series comparisons. The proposed simulations will have a ground breaking impact on research for the entire paleoclimate community. The major scientific questions to be addressed in this project are: (1) What are the relationships between the water isotopic geotracers and climate changes over the globe? (2) How does the climate system respond to transient climate forcings of the last deglaciation, and what is the contribution from the insolation, atmospheric greenhouse gases, continental ice sheets? To accomplish this, a version of the CESM, enabled with isotopic water tracers, will be run in iCESM for the period 21,000 to 11,000 years ago, forced by realistic forcings in combination and individually. One central task of the proposed transient simulations is to explore a new paradigm of model-data comparison in close collaboration with the data community, focusing on direct time series comparisons of isotopes.

Modeling Regional Climate Change and Its Effects on the Ecosystems and Ecosystem Services in New Hampshire

Project lead: Matthew Huber, University of New Hampshire
Yellowstone allocation: 12 million core-hours
Sponsor: NSF

The New Hampshire (NH) Experimental Program to Stimulate Competitive Research (EPSCoR), Ecosystems and Society project is a National Science Foundation (NSF) funded $12 million project studying the impacts of climate change on regional terrestrial and aquatic ecosystems and ecosystems services and evaluating the cost of these impacts on regional economy. To simulate potential regional impacts of climate change, we will utilize general circulation model (GCM) simulations of the future using a high impact representative concentration pathway (RCP) and we will dynamically downscale these predictions using a regional climate model. The output from the regional climate model will be used to drive smaller scale ecosystem and economy models to simulate the ecosystems’ response to climate change and the cost of these changes on regional economy.