University of Reading 2007www.nerc-essc.ac.uk/~rpa Surface radiative fluxes: comparison of NWP/Climate models/reanalyses with.

Slides:

Advertisements

Similar presentations

WGCM CFMIP/IPCC Climate Sensitivity Meeting, Exeter, April 2004 Decadal Variability in Water Vapour Richard Allan, Tony Slingo Environmental Systems Science.

Advertisements

© University of Reading Richard Allan Department of Meteorology, University of Reading Thanks to: Jim Haywood and Malcolm.

Dust and vapour cloud the view Richard Allan Environmental Systems Science Centre, University of Reading, UK Thanks to Tony Slingo, Ruth Comer, Sean Milton,

© University of Reading Chapman Conference on Atmospheric Water Vapor and Its Role in Climate Tropospheric Water Vapour and.

University of Reading Improved understanding of how rainfall responds to a warming world Richard Allan Environmental Systems.

University of Reading 2007www.nerc-essc.ac.uk/~rpa Monitoring satellite observations and model simulations of changes in the atmospheric.

Figure 1: Using GERB and SEVIRI data to evaluate the Met Office NWP model in near-real time; example SINERGEE comparisons for 8 th March 2006 at 1200 UTC.

Current Changes in the Tropical Precipitation and Energy Richard P. Allan Department of Meteorology, University of Reading Thanks to Brian Soden, Viju.

IRS2004, Busan, August 2004 Using Satellite Observations and Reanalyses to Evaluate Climate and Weather Models Richard Allan Environmental Systems Science.

Current Changes in Tropical Precipitation Richard P. Allan Department of Meteorology, University of Reading Thanks to Brian Soden, Viju John, William Ingram,

© University of Reading 2009 EUMETSAT Monitoring changes in precipitation and radiative energy using satellite data and.

University of Reading 2007www.nerc-essc.ac.uk/~rpa Present day changes in tropical precipitation extremes in models and observations.

© University of Reading Monitoring and understanding current changes in the global energy & water cycles Richard Allan.

3) Empirical estimate of surface longwave radiation Use an empirical estimate of the clear-sky surface downward longwave radiation (SDLc) to estimate the.

Current Changes in the Global Water Cycle Richard P. Allan Department of Meteorology, University of Reading Thanks to Brian Soden, Viju John, William Ingram,

1 Evaluating water vapour in HadAM3 using 20 years of satellite data Richard Allan, Mark Ringer Met Office, Hadley Centre for Climate Prediction and Research.

Changes in clear-sky longwave radiative cooling in the atmosphere Richard Allan Environmental Systems Science Centre, University of Reading,

NCAS-Climate Talk 15 th January 2010 Current Changes in the Global Water Cycle Richard P. Allan Diffusing slowly to Met Department/NCAS-Climate from ESSC.

Links Between Clear-sky Radiation, Water Vapour and the Hydrological Cycle Richard P. Allan 1, Viju O. John 2 1 Environmental Systems Science Centre, University.

Evaluating the Met Office global forecast model using Geostationary Earth Radiation Budget (GERB) data Richard Allan, Tony Slingo Environmental Systems.

1 Evaluating climate model using observations of tropical radiation and water budgets Richard P. Allan, Mark A. Ringer Met Office, Hadley Centre for Climate.

Evaluating the Met Office global forecast model using GERB data Richard Allan, Tony Slingo Environmental Systems Science Centre, University of Reading.

Implications of trends and variability in low-level water vapour Richard P. Allan Department of Meteorology/NCAS climate, University of Reading Thanks.

EUMETSAT 2006 Helsinki Exploitation of GERB/SEVIRI data for evaluation of the Met Office global forecast model Richard Allan, Tony Slingo Environmental.

Comparisons between GERB and the Met Office NWP model Richard Allan, Tony Slingo Environmental Systems Science Centre, University of Reading Sean Milton,

RMS 18 th June 2003 Evaluating moisture in the Hadley Centre Climate Model using 20 years of satellite data Richard Allan Environmental Systems Science.

Atmospheric clear-sky longwave radiative cooling and precipitation Richard Allan Environmental Systems Science Centre, University of Reading, UK.

ESSC Seminar, October 18, 2007© University of Reading 2007www.reading.ac.uk Intensification of the tropical hydrological cycle? Richard P. Allan Environmental.

Trends in Water Cycle meeting, Paris, November 2004 Cloud and water vapour variability: models, reanalyses and observations Richard P. Allan and Tony Slingo.

University of Reading 2007www.nerc-essc.ac.uk/~rpa Observed and simulated changes in water vapour, precipitation and the clear-sky.

Robin Hogan Julien Delanoe University of Reading Remote sensing of ice clouds from space.

SYSTEMATIC BIASES 3-hourly comparisons of top of atmosphere radiation from GERB and the Met Office global forecast model Systematic biases in model fluxes.

Changes in Water Vapour, Clear-sky Radiative Cooling and Precipitation

IPCC Workshop on Climate Sensitivity, Paris, July 2004 Exploiting observations of water vapour to investigate simulations of water vapour feedback processes.

GERB/CERES Meeting 2006 Exeter Evaluation of clouds and radiation in the Met Office global forecast model using GERB/SEVIRI data Richard Allan, Tony Slingo.

An Evaluation of the Surface Radiation Budget Over North America for a Suite of Regional Climate Models Student: Marko Markovic Director: Colin Jones Université.

Water Vapor and Cloud Feedbacks Dennis L. Hartmann in collaboration with Mark Zelinka Department of Atmospheric Sciences University of Washington PCC Summer.

Earth-Atmosphere Energy Balance Earth's surface absorbs the 51 units of shortwave and 96 more of longwave energy units from atmospheric gases and clouds.

The RADAGAST project Tony Slingo Environmental Systems Science Centre University of Reading Background and motivation Aims Methodology GIST 23, Deutscher.

Radiation Group 3: Manabe and Wetherald (1975) and Trenberth and Fasullo (2009) – What is the energy balance of the climate system? How is it altered by.

3 May 2007 GIST May Professor John Harries, Professor John Harries, Space and Atmospheric Physics group, Blackett Laboratory, Imperial College,

Land Surface Analysis SAF: Contributions to NWP Isabel F. Trigo.

Overview of the “Geostationary Earth Radiation Budget (GERB)” Experience. Nicolas Clerbaux Royal Meteorological Institute of Belgium (RMIB) In collaboration.

Modern Era Retrospective-analysis for Research and Applications: Introduction to NASA’s Modern Era Retrospective-analysis for Research and Applications:

ISCCP at its 30 th (New York, 22 – 25 April, 2013) Congratulations to the “Core Team” and to “Patient Outside-Supporters”: Our best wishes for a perspective.

Research Needs for Decadal to Centennial Climate Prediction: From observations to modelling Julia Slingo, Met Office, Exeter, UK & V. Ramaswamy. GFDL,

Promoting Satellite Applications in the TPE Water and Energy Cycle Studies: Chance and Challenge Kun Yang Institute of Tibetan Plateau Research Chinese.

Dust Longwave Forcing from GERB and SEVIRI Vincent Gimbert, H.E. Brindley, J.E. Harries Imperial College London GIST 26, 03 May 2007, RAL, Abingdon Thanks.

Radiative Atmospheric Divergence using ARM Mobile Facility, GERB data and AMMA stations –led by Tony Slingo, ESSC, Reading University, UK Links the ARM.

RMIB involvement in the Geostationary Earth Radiation Budget (GERB) and Climate Monitoring SAF projects Nicolas Clerbaux Remote sensing from Space Division.

Ocean Surface heat fluxes

Page 1© Crown copyright 2006 Modelled & Observed Atmospheric Radiation Balance during the West African Dry Season. Sean Milton, Glenn Greed, Malcolm Brooks,

ISCCP SO FAR (at 30) GOALS ►Facilitate "climate" research ►Determine cloud effects on radiation exchanges ►Determine cloud role in global water cycle ▬

MODIS Science Team Meeting, Land Discipline (Jan. 27, 2010) Land Surface Radiation Budgets from Model Simulations and Remote Sensing Shunlin Liang, Ph.D.

Using GERB and CERES data to evaluate NWP and Climate models over the Africa/Atlantic region Richard Allan, Tony Slingo, Ali Bharmal Environmental Systems.

LIMITLESS POTENTIAL | LIMITLESS OPPORTUNITIES | LIMITLESS IMPACT Copyright University of Reading AIR-SEA FLUXES FROM ATMOSPHERIC REANALYSES Richard Allan.

Heating of Earth's climate continues in the 2000s based upon satellite data and ocean observations Richard P. Allan 1, N. Loeb 2, J. Lyman 3, G. Johnson.

Influence of climate variability and

Radiative biases in Met Office global NWP model

Dust, vapour & cloud in greenhouse Earth

Monitoring current changes in precipitation and Earth’s radiative energy balance using satellite data, reanalyses and models Richard P. Allan1 | Viju.

Panel: Bill Large, Bob Weller, Tim Liu, Huug Van den Dool, Glenn White

Observed and Simulated Decadal Variability in Clouds and Water Vapour Richard Allan, Tony Slingo Environmental Systems Science Centre, University of Reading.

Changes in global net radiative imbalance

Current global and regional changes in atmospheric water vapour

New energy budget estimates at top of Earth’s atmosphere and surface

New energy budget estimates at top of Earth’s atmosphere and surface

Ming-Dah Chou Department of Atmospheric Sciences

Environmental Systems Science Centre, University of Reading

Presentation transcript:

University of Reading 2007www.nerc-essc.ac.uk/~rpa Surface radiative fluxes: comparison of NWP/Climate models/reanalyses with remote sensing estimates Richard P. Allan Environmental Systems Science Centre, University of Reading, UK

University of Reading 2007www.nerc-essc.ac.uk/~rpa Earths energy balance Kiehl and Trenberth, 1997; Also IPCC 2007 tech. summary, p.94

University of Reading 2007www.nerc-essc.ac.uk/~rpa Determinants of surface radiation FieldClimatologyDiurnaldecadal change Insolation Cloud Aerosol Ozone Water vapour Temperature Water vapour Cloud aerosol GHG SW LW

University of Reading 2007www.nerc-essc.ac.uk/~rpa Methods of model surface flux evaluation NWP/Climate model Surface flux observations Physics Reanalyses Satellite data Conventional observations RT models Empirical models Other models

University of Reading 2007www.nerc-essc.ac.uk/~rpa Ground Based Observations Evaluation of NWP/Climate models ARM siteARMModel Barrow Lamont++ Darwin Manus ** Peter Henderson et al. Atmospheric emissivity Column water vapour (cm)

University of Reading 2007www.nerc-essc.ac.uk/~rpa Bodas et al. (2008) J. Climate (see also e.g., Wild et al. (2001) J Climate, etc) Excellent time resolution Direct observations Scaling up issues Poor spatial coverage Instrumental uncertainty

University of Reading 2007www.nerc-essc.ac.uk/~rpa Empirical estimates Based on physics Use surface observations to calibrate –e.g. Prata (1996) QJ Royal Meteorol Soc Clear-sky surface down longwave Column integrated water vapour Screen-level temperature Atmospheric emissivity

University of Reading 2007www.nerc-essc.ac.uk/~rpa NCEP clear and cloudy surface down longwave and Prata empirical estimate using observed T 2m and column integrated water vapour Niamey, Niger Empirical formulas are valuable tools in understanding physical processes determining radiative flux variations

University of Reading 2007www.nerc-essc.ac.uk/~rpa Good quality clear-sky fluxes? Range in estimates of clear- sky surface net longwave radiation… SRB (82 Wm -2 ) > NCEP (80 Wm -2 ) > ERA40 (73 Wm -2 ) > SSM/I empirical Reanalyses Allan (2006) JGR

University of Reading 2007www.nerc-essc.ac.uk/~rpa Robust relationship between clear-sky net surface LW flux (SNLc) and column water vapour (CWV) ERA40 NCEP Allan (2006) JGR dCWV (mm) ~1.3 Wm -2 mm -1 Clear ~1.5 Wm -2 mm -1 CWV (cm) SNL (Wm -2 ) Slingo et al (2008) JGR Global: reanalysesSahel, Africa: observations

University of Reading 2007www.nerc-essc.ac.uk/~rpa Interannual/Decadal changes: Homogeneity an issue Surface fluxes available globally on model grids Observational basis through data assimilation Model/observational errors; require validation Changes in quality of observing system may lead to spurious variability Allan (2007) Tellus

University of Reading 2007www.nerc-essc.ac.uk/~rpa Reanalysis cloud properties unrealistic Cloud components of surface fluxes poor ERA40-ISCCP total cloud difference ERA40 – satellite data (below) Allan et al. (2004) JGR

University of Reading 2007www.nerc-essc.ac.uk/~rpa Remote sensing of surface fluxes Use satellite (and other) retrievals of important parameters (e.g. cloud, T, q) Input to radiative transfer codes Surface fluxes on model/satellite grids –e.g. ISCCP clouds/reanalysis atmosphere: Zhang et al. (2004) JGR, Stackhouse et al (GEWEX), Pavlakis et al. (2004) Atmos Chem Phys

University of Reading 2007www.nerc-essc.ac.uk/~rpa Bodas et al. (2008) J. Climate HadGAM1-Obs: Albedonet SW Surface Down LWColumn Water Vapour

University of Reading 2007www.nerc-essc.ac.uk/~rpa Spurious changes in ISCCP clouds Surface fluxes: Issues with cloud-overlap, calibration and coverage/angular effects Norris and Slingo (2008) FIAS

University of Reading 2007www.nerc-essc.ac.uk/~rpa Remote sensing of surface fluxes e.g. surface longwave What the surface sees Cloud base Column water vapour Tair IR satellite Cloud top Tskin (when clear) microwave satellites Humidity temperature (when clear) Cloud liquid water precipitation, wind. Atmospheric temperature / water vapour

University of Reading 2007www.nerc-essc.ac.uk/~rpa Comparisons of NWP model and satellite estimates of: Cloud liquid water Water vapour Indirect evaluation of surface fluxes –Parameters important for surface LW (and SW) radiation –Allan et al. (2008) QJRMS

University of Reading 2007www.nerc-essc.ac.uk/~rpa Constraining model (based on remote sensing estimates) using surface/satellite observations Work with: Nicky Chalmers & Robin Hogan Model v GERB/MSG Model v ARM

University of Reading 2007www.nerc-essc.ac.uk/~rpa RADAGAST/AMMA case study 1200GMT, 8 March 2006 RADAGAST project:

University of Reading 2007www.nerc-essc.ac.uk/~rpa Shortwave fluxesLongwave fluxes Diurnal cycle in surface fluxes –Solar/geometry; Temperature response; Atmosphere response Daily variability –Advection of air-masses; Aerosol cloud effects Important to simulate in models Important to correct for in remote sensing estimates

University of Reading 2007www.nerc-essc.ac.uk/~rpa Radiative transfer models underestimate the solar absorption in the atmosphere during March 2006 dust storm Slingo et al. (2006) GRL, 33, L24817

University of Reading 2007www.nerc-essc.ac.uk/~rpa Special issue on RADAGAST under review for JGR-Atmospheres (A. Slingo et al.) Using surface observations (and models) improves understanding of physical processes; An indirect method of model evaluation

University of Reading 2007www.nerc-essc.ac.uk/~rpa Evaluating model climate change responses CMIP3 CMIP3 volcanic NCEP ERA40 SSM/I-derived ~ +0.7 Wm -2 decade -1 SNLc (Wm -2 ) Changes in clear-sky surface net longwave flux in coupled climate models, reanalyses and empirical estimates

University of Reading 2007www.nerc-essc.ac.uk/~rpa Linear fit dSNLc/dTs ~ 3.5±1.5 Wm -2 K -1 dCWV/dTs ~ 3.0±1.0 mm K -1 CMIP3 non-volcanicCMIP3 volcanic Reanalyses/ ObsAMIP3 Models, reanalyses and observations show increased surface net downward longwave with warming due to increased water vapour

University of Reading 2007www.nerc-essc.ac.uk/~rpa Increases in water vapour enhance clear- sky longwave radiative cooling of atmosphere to the surface This is offset by enhanced absorption of shortwave radiation by water vapour Changes in greenhouse gases, aerosol and cloud alter this relationship… Tropical oceans

University of Reading 2007www.nerc-essc.ac.uk/~rpa Sensitivity test: tropical oceans Clear-sky Longwave shortwave TOA SFC ATM ATM 1K increase in tropospheric T, constant RH Greenhouse gas changes from 1980 to 2000 assuming different rates of warming

University of Reading 2007www.nerc-essc.ac.uk/~rpa Conclusions Evaluation of surface fluxes in models crucial but problematic (climatology, diurnal cycle, trends) Surface observations: –Excellent time-resolution –Upscaling issues, spatial coverage poor Reanalyses limitations: clouds/variability Remote sensing estimates –Good spatial (and temporal) coverage –Measure accurately quantities important for surface fluxes; need to consider variety of time-scales Analysis of surface/satellite data can help to improve physical processes in models better surface fluxes

University of Reading 2007www.nerc-essc.ac.uk/~rpa Extra Slides

University of Reading 2007www.nerc-essc.ac.uk/~rpa Evaluation of diurnal cycle in NWP model using surface observations Milton et al. (2008) JGR accepted Niamey ARM station (RADAGAST/AMMA)

University of Reading 2007www.nerc-essc.ac.uk/~rpa Diurnal effects: near surface temperature NightDay Temperature Altitude

University of Reading 2007www.nerc-essc.ac.uk/~rpa Near surface temperature: diurnal cycle error Missing physics?

University of Reading 2007www.nerc-essc.ac.uk/~rpa Diurnal skin temperature effects are also apparent for oceans (clear, calm conditions) Allan (2000) J.Climate

University of Reading 2007www.nerc-essc.ac.uk/~rpa Surface downward LW sensitive to moisture changes in lowest levels and temperature changes close to the surface Sensitivity of surface downwelling LW to temperature and moisture changes in 50 hPa vertical levels 1K temperature increase; moisture increased to conserve Relative Humidity

University of Reading 2007www.nerc-essc.ac.uk/~rpa Window region crucial in determining changes in surface net LW flux Spectral signatude of clear-sky surface net longwave radiation

University of Reading 2007www.nerc-essc.ac.uk/~rpa Increased moisture enhances atmospheric radiative cooling to surface ERA40 NCEP Allan (2006) JGR 111, D22105 SNLc = clear-sky surface net down longwave radiation CWV = column integrated water vapour dCWV (mm) ~1.4 Wm -2 mm -1

University of Reading 2007www.nerc-essc.ac.uk/~rpa Evaluation of climate model sensitivity SNLc = clear-sky surface net down longwave radiation CWV = column integrated water vapour dSNLc/dCWV ~ W kg -1

University of Reading 2007www.nerc-essc.ac.uk/~rpa Also true for unique meteorological environments (e.g. Niamey, Radagast project, Slingo et al.) –Here water vapour & temperature anti-correlated over the seasonal cycle Clear ~1.5 Wm -2 mm -1

University of Reading 2007www.nerc-essc.ac.uk/~rpa Impact of clouds on surface LW radiation Smaller cloud LW effect in cloudy deep tropics due to water vapour path

University of Reading 2007www.nerc-essc.ac.uk/~rpa Surface cloud LW effect: observations and NWP model - Higher water path: smaller cloud effect - More cloud, lower/warmer cloud-base: higher cloud effect

University of Reading 2007www.nerc-essc.ac.uk/~rpa

University of Reading 2007www.nerc-essc.ac.uk/~rpa Dimming to brightening simulated in HadGEM1 climate model (Bodas et al.)

University of Reading 2007www.nerc-essc.ac.uk/~rpa

University of Reading 2007www.nerc-essc.ac.uk/~rpa Direct evaluation of models using surface observations Allan (2000) J Climate Barrow, Alaska

University of Reading 2007www.nerc-essc.ac.uk/~rpa

University of Reading 2007www.nerc-essc.ac.uk/~rpa

University of Reading 2007www.nerc-essc.ac.uk/~rpa

University of Reading 2007www.nerc-essc.ac.uk/~rpa

University of Reading 2007www.nerc-essc.ac.uk/~rpa

University of Reading 2007www.nerc-essc.ac.uk/~rpa

University of Reading 2007www.nerc-essc.ac.uk/~rpa Bodas et al. (2008) J. Climate

University of Reading 2007www.nerc-essc.ac.uk/~rpa SST Water vapour Clear net LW down at surface Testing climate model simulations of current variability (tropical oceans)