Page 1© Crown copyright 2007 Current Activities and Plans in NWP Clive Wilson, 19 September 2007

© Crown copyright 2007 Page 1

Current Activities and Plans in NWP

Clive Wilson, 19 September 2007


New Chief Executive from 17 September

Mark Hutchinson returning to Ministry of Defence after secondment to the Met Office

John Hirst, BA(Economics) No Atmospheric Science/Meteorology experience History:

“CEO of Premier Farnell from 1998-2005 Built an excellent leadership team redefined the business both operationally and financially repositioned it so as to grow market share and earnings. At ICI, during a period of high revenue growth, and undertook a

series of successful acquisition and merger negotiations” "I am very excited at the prospect of becoming Chief Executive of

an organisation at the forefront of one of the world's great issues. The Met Office is a truly world-class science organisation, with an excellent reputation, built on the talents of the staff who work for it. Working together, I am confident that we can harness our leading science base to enhance our impact and deliver even greater value to our public and commercial customers"

Probably means more emphasis on commercial activity and consultancy

© Crown copyright 2007 Page 4© Crown copyright 2007

CRM

SCM

OBS

UNIFIED MODEL

AQUAPLANET DYN CORE JULESIdealised

NWP &THORPEX

SEASONALDECADAL

CLIMATE

Km Scale

Global

Regional CLIMATEREGIONAL

NWPREGIONAL

Data Assimilation

Evaluation

Forcing

Evaluation

NWP configurations


2007 Operational Forecast Systems

UK 4km

Regional 12km+EPS

24member,24km

Global 40km+EPS 24member,90km

50 levels

38 levels


Model characteristics

N144 38LMOGREPS-G

N320 50LDeterministic

Grid points 288 (EW) x 217 (NS)

640 (EW) x 481 (NS)

Resolution: Mid-latEquator

~90 km 138 km

~ 40 km 63 km

Time-step 20 min 15 min

Same resolution to 15km


Limited area models

North Atlantic European (NAE)

UK 4 km 1.5km “On Demand”

Grid points/levels

600 x 360x38L 288x 360x38L 300 x 300x38L

Resolution 0.11o (12km) 0.036o (4km) .0135o(1.5km)

Time-step 5 min 100 s 50 s

Forecast runs/length

00,06,12,18 UTCT+48

03,09,15,21 UTCT+36 (+42 21UTC)

03 UTCT+18

Data assimilation

4DVAR+MOPS 3DVAR+MOPS Interpolated from UK4

Lateral boundaries

Global (T-6 run)hourly

NAE (T-3 run)30 min

UK4 (contemporary)

30 min


1

2

3

4

7

6

98

5

1.5km “On demand”

Global ModelSean Milton


Recent Global Model Upgrades

G37 Aug 2005 Implementation of soil moisture nudging scheme G38 Dec 2005 Resolution upgrade - 40km (N320) , 50 levelsG39 Mar 2006 Re-introduce AIRS and ERS-2 Scat. Replace Met-7 Satwinds with Met-8 satwinds. Tropical improvements - Physics upgrade (adaptive detrainment convection, improved surface

transfer in Marine BL)G40 Jun 2006 Improved soil moisture nudging over bare soil G41 Sep 2006 Satellite changes - SSMIS and GPS ROG42 Dec 2006 Increased use of ATOVS & Introduction of GPS RO.Model Spectral Gravity wave drag & Stratospheric stability package.Convective cloud decay.G43 Mar 2007 Introduce METOP data to replace NOAA15 data (early introduction 16th Jan) G44 May 2007 Introduce biogenic aerosols climatology bare soil albedo based on MODIS moisture flows into level below saturated or frozen soli rather than lost as run-off seasonal varying leaf area index (LAI) Assimilation of COSMIC GPS radio occultation data


N.Hemisphere T+24 RMSE – MSLPVerification vs. analysis


S.Hemisphere T+24 RMSE – MSLPVerification vs. analysis


Model Cycle G44 Operational 15 May 2007

© Crown copyright 2007

Problem – Poor Summer performance : warm bias over land, MSLP too low, NWP index poor vs other centres.

Global Model Physics Changes (also in HadGEM2) Change bare soil albedo – MODIS. Change runoff formulation in MOSES2 – deep soil layers wetter. Introduce biogenic aerosol – oxidation of hydrocarbon emissions from

plants. Introduce seasonally varying leaf area index (LAI). Two corrections to convective cloud

cloud phase was set according to the temperature at the top of the model rather than the top of the cloud. All convective cloud erroneously seen as ice cloud within the radiation scheme.

deep convective clouds are seen as liquid by the radiation scheme below the freezing level.

Satellite Observations – COSMIC (GPS radio occultation)


Model Cycle G44Improvements

in Model SurfaceAlbedo (vs. MODIS)

(Work in collaboration with U. Swansea as part of CLASSIC project)

© Crown copyright 2007 Page 18© Crown copyright 2004© Crown copyright 2007

Impact of Improving Model Surface Albedo Model cycle G44 – from 15 May 2007

UM too dark UM too bright

Model – MODIS (Annual) surface albedo Impact new surface albedo on 1.5m TempsT+48 Forecast

Prior to May 2007 physics changes the model surface albedo was too bright across the Middle East & SW Asia. This tends to make model too cold near surface as too much solar radiation is reflected back to space

Impacts on forecast temperatures – general warming of 1.5m temperatures throughout the Middle East & SW Asia– max values of order 3K over Iran and around Red Sea.


Screen T warm bias over land – Improvements with Cycle G44 Physics Package operational from May 2007JJA 2006 trials

Biases in screen T over NH land points : 1 Jun 2006 to 5 Aug 2006

Improved cycle G44 “Physics” reduces the summer warm bias

Summer warm bias not evident prior to soil nudging as “too moist”soil climatology kept surface moist and cool


Future Upgrades to Global Model

Nov 2007 Introduce IASI into data assimilation.

New OSTIA SST analysis. 2008

Enhance vertical resolution from 50L to 70L.

Improved soil properties & Van Genuchten soil hydrology.

PC2 cloud scheme.

Improved seasonally varying aerosol climatology (Mineral dust parametrization in Southern Asia Model)

Introduce snow analysis and improved snow parametrization (e.g. snow canopy) 2009

Enhance horizontal resolution – 40km to 25km

Turbulence based convection scheme – shallow, congestus, (deep?)

1 hour radiation timestep – currently 3 hours in global model. 2011

Enhance vertical resolution – 70L to 90L.

ENDGAME – Even Newer Dynamics

Limited Area modelsClive Wilson, Mike Bush, Jorge

Bornemann


Regional v Global


NAE recent developments

E10 13th December 2005 ATOVS & Satwind changes

E11 14th March 2006 Introduction of 4DVAR

E12 14th June 2006 Data assimilation upgrade

E13 26th September 2006 Schedule change (replace U.K Mesoscale model) Introduction of AIRS SST improvements Physics upgrade

E15 6 March 2007 Aerosol changes for visibility New balanced lbcs w-based convection instead or RH based

E16 15 May 2007 Reduced domain

E17 14 August 2007 Extra Perturbation Forecast model physics (convection)


NAE model cycle E11 – 14th Mar 2006

4D-VAR introduced 500hPa Height biases and RMS errors reduced.


NAE model cycle E11 – 14th Mar 2006

4D-VAR introduced 250hPa Wind biases and RMS Vector errors reduced.


RH-based CAPE closure

Until PS14 the NAE and Global models shared the same RH dependent CAPE closure to the convection scheme.

RH based closure was introduced to target grid point storms (GPS) by shortening the 30 minute CAPE timescale when RH>80%.

However the higher resolution of the NAE model compared to the Global model means that fronts are better resolved.

The higher associated RH along the fronts leads to CAPE timescales as small as 5-10 minutes even though there are no GPS along the front.

The effect of this short timescale is to produce noisy (both spatially and temporally) convective precipitation rates.


CAPE timescale as a function of RH


W-based CAPE closure impact on the NAE

The new vertical velocity based CAPE closure also targets GPS, but does not speed up convection where GPS are not occurring.

The CAPE closure is timescale is fixed at 30 minutes and does not reduce unless the vertical velocity exceeds 1m/s.

This produces smoother convective precipitation patterns and a redistribution between large scale and convective precipitation.

Case study testing has shown the w-CAPE scheme to improve precipitation and cloud scores

March 2007 U.K Index results show best ever ppn and cloud scores!


W-CAPE versus RH-CAPE – E15 6 March 2007


CAPE timescale as a function of W


W-based CAPE closure impact on the NAE

RH dependent CAPE (red) and w-CAPE (blue) 6hr ppn accumulation ETS scores averaged over 32 case studies


19th October 2006 case study at 15Z


Reduced domain to afford 70 levels


UK4 changes (2007)

U4.09 August 2007Physics upgrade (catch up with NAE)

Introduce radiation on slopes: including slope aspect and angle in direct solar radiationAerosol changes for visibilityNew balanced lbcs

Dec 2007Increase vertical resolution (70 levels)

Update Covstats (because of resolution change)

Planned:Introduce seasonal variability in Leaf Area Index

Revised soil moisture analysis (Van Genuchten soil hydraulics in the land surface scheme).

Split urban tile type into rooftops and street canyons (long term)

Review convection scheme (research ongoing)


70 levels for UK4

Lowest 4km


70 levels upgrade (Verification of 16 cases)

MSLP

Surface Temperature


70 levels upgrade (Verification of 16 cases)

Cloud fraction

10m wind


70 levels upgrade (Improved vertical structure ?)


70 levels upgrade (Subjective assessment)

38 L 70 L

Fog overdone in both forecasts

Plans


Global & NAE 70 Levels – March 2008

Lowest 4km


Supercomputer Procurement Plans

• Invitation to Tender Issued – Aug 2007

• Selected Supplier – May 2008

• System Installation – Q4 2008

• System Acceptance – Q1 2009

• Expectation of a 5 year contract with phased upgrades

• Initial System expected to provide >100TFlop peak with performance for applications ~6 relative to current NEC SX8


Met Office Production NWP Configuration Plans

2009 Global NWP 25km , 70 levels Global Ensemble, 50-60km , 70 levels to 15 days NAE ensemble 12km, 70L, 24M, 54hr UK NWP 1.5km , 70 levels, 36hr

2011 Global NWP 16-18km , 100 levels Global Ensemble, 100L, 50km to 15 days NAE ensemble 12km, 100L, 24M, 54hr UK NWP 1.5km ensemble (6 members+lagged) UK AQ 12km, 38L, 60tracers, 48hr f/c daily x2 DA; x1.4 physics/aerosol (relative to 5/07)

Even Newer Dynamics- EndgameNigel Wood


Aims of ENDGame

ENDGame: Even Newer Dynamics for Global atmospheric modelling of

the environment

Build on the foundations of the New Dynamics

Primary aim is improved robustness.

Secondary aims are: Improved accuracy

Retain greater non-linearity Reduce the need for significant off-centring of α

parameters Maintain/improve conservation

Inherent SL mass conservation Inherent water species + tracer conservation

While maintaining/improving efficiency


Improved accuracy

Iterative SISL scheme – Diamantakis et al (QJ 2007)

Following discrete normal mode analysis of Thuburn and Staniforth (MWR, 2004):

v (and v alone) to be held at poles (cf. present u, w and all scalars) improved energy properties

Coriolis terms based on mass flux variables improved Rossby mode propagation


Conservation

SLICE:Semi-Lagrangian Inherently Conserving and

Efficient advection scheme =

- SL finite-volume scheme

- Made efficient by applying a cascade approach

- i.e. a flow dependent dimensional splittingAll conserved variables advected via SLICEAll other variables advected using full 3D

interpolating scheme

Flux form for gradient operators


Switchable options

Retain deep-atmosphere, nonhydrostatic formulation

But introduce switches to investigate sensitivities:

Deep-atmosphere / shallow-atmosphere / Cartesian geometries

Hydrostatic / nonhydrostatic equationsSpherical / spheroidal coords Uniform / stretched grids Intrinsic mass & tracer conservation (on / off)


Where are we? And whither next

Now developing two 2D prototype models:Shallow-water model;Vertical slice model

Develop 3D prototype (2008)

Move to UM framework, couple to physics, DA (2009…)

Testing for operational implementation (2010/11?)


Questions & Answers


New Chief Executive from 17 September

Mark Hutchinson returning to Ministry of Defence after secondment to the Met Office

John Hirst, BA(Economics) No Atmospheric Science/Meteorology experience History:

“CEO of Premier Farnell from 1998-2005 Built an excellent leadership team redefined the business both operationally and financially repositioned it so as to grow market share and earnings. Formerly at ICI , CEO of the global Speciality Chemical Division during a period of high revenue growth, and undertook a series of

successful acquisition and merger negotiations” "I am very excited at the prospect of becoming Chief Executive of

an organisation at the forefront of one of the world's great issues. The Met Office is a truly world-class science organisation, with an excellent reputation, built on the talents of the staff who work for it. Working together, I am confident that we can harness our leading science base to enhance our impact and deliver even greater value to our public and commercial customers"

Probably means more emphasis on commercial activity and consultancy

Documents

Page 1© Crown copyright 2007 Current Activities and Plans in NWP Clive Wilson, 19 September 2007