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This article provides an overview of the Global Land Atmosphere System Study (GLASS) and explores its potential links with the Seasonal to Sub-seasonal (S2S) prediction. GLASS aims to improve estimates, model representation, and understanding of land/atmosphere feedbacks and predictability. It also highlights ongoing and future GLASS projects.
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S2S Meeting, Feb. 4-6, 2013, Exeter, UK Global Land Atmosphere System Study (GLASS) overview and potential links with S2SAaron Boone (CNRM-GAME, Météo-France)and Joe Santanello (NASA-GSFC)
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Global Land Atmosphere System Study (GLASS) The aim of GLASS is to promote community activities that improve: our best estimates and the model representation of state variables our understanding of land/atmosphere feedbacks our understanding of the role of land surface in predictability. To best achieve these aims, GLASS has been re-structured into three elements:
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Global Land Atmosphere System Study (GLASS) The aim of GLASS is to promote community activities that improve: our best estimates and the model representation of state variables our understanding of land/atmosphere feedbacks our understanding of the role of land surface in predictability. To best achieve these aims, GLASS has been re-structured into three elements:
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Global Land Atmosphere System Study (GLASS) The aim of GLASS is to promote community activities that improve: our best estimates and the model representation of state variables our understanding of land/atmosphere feedbacks our understanding of the role of land surface in predictability. To best achieve these aims, GLASS has been re-structured into three elements:
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK GLASS Projects : • Ongoing • ALMIP2 – Links to GHP • GLACE2 – Links to S2S? • LUCID2 – Links to iLeaps • Launching in next 12 months: • GSWP3 – Links to carbon community • PILDAS – Links to WGNE • GLASS/GABLS coupling – Links to GASS • PALS benchmarking – Links to GHP • Being planned • LoCo SGP testbed
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Global Land Atmosphere System Study (GLASS) • PILDAS (Project for the Intercomparison of Land Data Assimilation Systems) • PILDAS is expected to launch in early 2013, once participants from all the major operational NWP centers have confirmed participation. • The experimental design is nearly complete: a pilot study is underway by the project lead to use 2 LSMs with 1 DA algorithm in NASA’s LIS (Land Information System platform) • Phase-1 is focused on operational centers, synthetic obs, and different DA algorithms w/different LSMs for a 1/8 degree domain over the SGP. Later phases will focus on coupled DA systems and actual satellite observations from SMOS and SMAP. • GLASS will take the experimental plan and pilot results to WGNE to put pressure on centers that are not currently listed (e.g. UK Met). • PALS (Protocol for the Analysis of Land Surface models) • Benchmarking - evaluating land surface models and the data sets used to test them • Includes gap filling, empirical benchmarks, and automated metrics along with a large suite of Fluxnet data. • The joint GHP-GLASS project to demonstrate benchmarking through PALS is ramping up with a deadline to produce results for the AMS Annual Meeting and GEWEX Newsletter.
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Global Land Atmosphere System Study (GLASS) Global Land-Atmosphere Coupling Experiment -2 The 2nd phase of the Global Land-Atmosphere Coupling Experiment Overall goal: Determine the degree to which realistic land surface (soil moisture) initialization contributes to forecast skill (rainfall, temperature) at 1-2 month leads
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Global Land Atmosphere System Study (GLASS) GLACE-2 • 10 GCMs • • 100 start dates (1 Apr 1986 ... 15 Aug 1995) • • 10 members of 2 months runs • • 2 series • 1) Series 1: initial soil from pseudo obs • 2) Series 2: random initial soil
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Global Land Atmosphere System Study (GLASS) GLACE-2
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Global Land Atmosphere System Study (GLASS) GLACE-2
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Global Land Atmosphere System Study (GLASS) GLACE-2 • 10 GCMs • • 100 start dates (1 Apr 1986 ... 15 Aug 1995) • • 10 members of 2 months runs • • 2 series • 1) Series 1: initial soil from pseudo obs • 2) Series 2: random initial soil • • Main Diagnostics: • Difference in R2 relative to obs series 1 – series 2 • averaged for 15-day lead periods
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Global Land Atmosphere System Study (GLASS) Precipitation forecasts: Increase in skill due to land initialization (JJA) (conditioned on strength of local initial soil moisture anomaly)
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Global Land Atmosphere System Study (GLASS) Temperature forecasts: Increase in skill due to land initialization (JJA) (conditioned on strength of local initial soil moisture anomaly)
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Global Land Atmosphere System Study (GLASS)
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Global Land Atmosphere System Study (GLASS) • Conclusions: • Skill improvement in US better than in Europe (also potential predictability in US larger) • • Skill in temperature and precipitation increases mainly in • areas where: • - the precipitation forcing quality is high (high station density gives • better initial soil moisture data) • - soil moisture is relatively extreme where potential predictability is high • - moderate skill (in places) even out to 2 months • Ongoing GLACE2 experiments from KNMI, ECMWF and ETH (Sonia Seneviratne, Gianpaolo Balsamo and Bart vd Hurk) are being performed for 2000-2010 in order to check possible signals emerging from known strong droughts in this period.
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Global Land Atmosphere System Study (GLASS) • Links between GLASS and S2S: • GLACE2 has given us some measure of and an approach to quantify the impact of land initialization on forecasts great care should be taken in the land is spun-up and initialized (and any diversity therein). • PILDAS will evaluate operational NWP centers' approaches to land DA, which ultimately will impact S2S-scale prediction through improved initialization (and ultimately coupled DA). • PALS Benchmarking is ramping up and through WGNE, the operational NWP centers have expressed interest in quantifying the 'goodness' of their land model components. In order to do this, one needs a majority of the list of the suggested variables, to benchmark the energy/water/carbon cycle.
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK GLASS-S2S: Suggested Addtional Land Surface Variables: Soils • Soil Heat Flux • Soil Moisture (&Temperature) at layer depths (or sfc vs. root zone) (z) • Soil ice content/frozen fraction (z) Evaporation Components • Total Evaporation (if both sublimation and liquid evaporation are concurrent) • Evaporation from Bare Soil • Transpiration • Interception Loss Vegetation • Some measure of Vegetation Coverage (LAI, GVF, etc.) • Prognostic Carbon Stores (z) Surface Snow • Snow depth (z) • Snow albedo Hydrology • Total runoff • River storage (if applicable) • Aquifer storage (if applicable) • Lake/flooded zone st. (if applicable) Static Land Surface Data: • Land Cover Type • Soil Type (z) • Soil Porosity (max soil moisture) (z) • Wilting Point (min soil moisture) (z) • Color key: • (z) Vertical dep. • Secondary • specified
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Dr. Joseph A. Santanello, Co-chairHydrological Sciences BranchNASA/GSFCGreenbelt, Maryland USAjoseph.a.santanello@nasa.govDr. Aaron A. Boone, Co-chairCentre National de Recherches MétéorologiquesCNRM-GAME, Météo-FranceToulouse, Franceaaron.boone@meteo.fr Global Land Atmosphere System Study (GLASS) GLASS Contacts:
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Global Land Atmosphere System Study (GLASS) Some GLACE2 references: Koster, R.D., S. P. P. Mahanama, T. J. Yamada, Gianpaolo Balsamo, A. A. Berg, M. Boisserie, P. A. Dirmeyer, F. J. Doblas-Reyes, G. Drewitt, C. T. Gordon, Z. Guo, J.-H. Jeong, W.-S. Lee, Z. Li, L. Luo, S. Malyshev, W. J. Merryfield, S. I. Seneviratne, T. Stanelle, B. J. J. M. van den Hurk, F. Vitart, and E. F. Wood (2011): The Second Phase of the Global Land-Atmosphere Coupling Experiment: Soil Moisture Contributions to Subseasonal Forecast Skill; J.Hydrometeorol., in press. Hurk, B.J.J.M. van den, F. Doblas-Reyes, G. Balsamo, R.D. Koster, S.I. Seneviratne en H. Camargo Jr, Soil moisture effects on seasonal temperature and precipitation forecast scores in Europe; Clim. Dyn., 2010, doi:10.1007/s00382-010-0956-2. Koster , R. D., S. Mahanama, T. Yamada, G. Balsamo, A.A. Berg, M. Boisserie, P. Dirmeyer, F. Doblas Reyes, G. Drewitt, C.T. Gordon, Z. Guo, J.H. Jeong, D.M. Lawrence, W.-S. Lee, Z. Li, L. Luo, S. Maleyshev, W.J. Merryfield, S.I. Seneviratne, T. Stanelle, B.J.J.M. van den Hurk, F. Vitart and E.F. Wood (2010), Contribution of land surface initialization to subseasonal forecast skill: First results from a multi-model experiment, Geophys. Res. Lett., 37, L02402, doi:10.1029/2009GL041677.
Seasonal to Sub-seasonal prediction Meeting, Feb. 4-6, Exeter, UK Global Land Atmosphere System Study (GLASS) • GLACE2-CMIP5 (Sonia Seneviratne and Bart vd Hurk) • Exp#1A and #1B of GLACE2-CMIP5 have been completed. This involved AR5 reruns of climate change projections using a 1971-2000 soil moisture climatology versus using a seasonal transient cycle of soil moisture and evaluated during the 2070-2100 period. • 3 groups have completed (GFDL, ECHAM, CESM) the full analysis and papers have been submitted. • Future phases of experiments involve land cover change. Highlights show that the imposed SM anomalies show similar regions as those projecting drought increase, and a larger impact of soil moisture change on daily max temperature. - Precipitation changes are less clear, and additional analysis will be conducted to analyze the feedbacks and water balance (E-P). • This is expected to be completed over the next 12 months.