Wiser – GFP – 2015-05-05

WISER and Flooding

A Weather climate change Impact Study at Extreme Resolution (WISER)

Alan Gadian, Ralph Burton, James Groves, Alan Blyth, Alex Meek & Stephen Mobbs NCAS, University of Leeds, UK

Greg Holland, Cindy Bruyere, James Done, Mari Tye, Ming Ge et al. NESL , NCAR, USA

Jutta Thielen et al. Climate Risk Management Unit, JRC

Engineering for Climate Change Extremes Partnership (ECEP)

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WISER (Weather climate change Impact Study at Extreme Resolution) is a project designed to use a numerical weather model (WRF), in a channel formulation. It is a regional climate model which will complete a global study (driven by ERA-Interim data from 1989-2000) and then for three selected decades in this century. Relative high resolution is required to resolve meso-scale weather patterns to reducing the errors / upscaling limitations. We will be making this an open dataset. Climate models have insufficient resolution to simulate “blocking” and regional meso-scale precipitation events, such as flash flooding events, which are critical in understanding the impacts of climate change.

 A  Key  Challenge.    

Why  do  we  need  to  spend  more  effort  studying  extreme  convec<ve  storms?              Since 1980, the increase in Meteorological disasters has accounted for most of the increase in “Natural Catastrophes”, with weather related costs increasing from 50$ Billion in 1980’s to 150$ billion in the last decade adjusting for inflation.  

Figure NI-1, ( Munich Re 2014) Red: Geophysical Events; Earthquakes, Tsunami, Volcanoes; Blue: Hydrological Events; Floods: Orange: Climate Events: Extreme Temperatures, Forest Fires; Green: Meteorological Events; Tropical, Extratropical, Convective and local storms

e.g. Before and after the storm event in Left Hand Canyon Heavy precipitation , September 2013 September 12th a record 9.08” was measured (annual average ~30”) with Sept 10th – 1.02” Sept 11th – 1.92” Sept 13th – 2.44” Sept 15th – 1.94”

Courtesy, Greg Holland, ECEP , (Engineering for Climate Extremes Partnership)

The WISER project is part of the ECEP consortia.

Courtesy Mari Tye, ECEP … the concept of planning for Graceful Failure

WISER is a an element which fits within the global challenge of ECEP

Holland, ECEP , 2014

The WISER project tackles part of this challenge.

Domain structure for the WISER. The outer domain (d01) resolution is 20km at +/-300 N/S and ~ 8km at 680N; the inner domain resolution defined as a factor of 5:1 smaller.

•  Opportunity to study extreme convective storms / precipitation.

•  Collaboration with European Flood Agency, JRC, to apply the results.

•  Collaboration with the “Engineering for Climate Extremes Partnership” (ECEP) lead by NCAR and with insurance and business interests.

Vision:- An interdisciplinary partnership with engineering, scientific, business and government expertise to develop robust well-communicated predictions on the impacts and climate extremes.

WISER Objectives •  Derive decadal time scale changes in general precipitation over UK & Western Europe. •  Predict changes in quantity and frequency of severe and hazardous convective rainfall and he frequency of flash flooding due to heavy convective precipitation.

Methodology

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We propose to embed a second set of nested simulations down to ~3 km resolution over Western Europe, in NCAR’s global dynamical framework. This will provide statistics for future severe weather of direct relevance to policy makers in Western Europe. We are computing model climatologies driven by:- •  ERA interim climate data for recent decades, 1980 to 2010, (Re-analysis studies. 1989-2000 in the instance) •  CESM / CAM climate data for the same decades to obtain offset and bias corrections (1989-2000 , 2020 - 30 and 2040 – 50)

•  Future climate scenarios in a future warmer climate, for future decadal periods for this century driven by CESM /CAM

Time-line (next 18 months):- Over the past 2 months computer time awards have been made ( ARCHER – UK supercomputer & Yellowstone – NCAR ) April 2015. Completed 1989 – 1994 simulation driven by ERA Interim data. May 2015 - Autumn 2015. 2020 – 2030 simulation driven by CCSM data. June 2015 – November 2015. 1995 – 2000 simulation, driven by ERA interim. December 2015 – December 2016. 2040 – 2050 simulation driven by CCSM. BIAS correction data summary completed. •  All data is available (for community use) at BADC (British Atmospheric Data

Centre). •  Data to be included in the ECEP data base. •  Data to be used in the EFAS flood model framework. •  Publications to be produced in late 2015 .

Left panel : Mean Annual OLR from the ERBE satellite measurements (years 1985 - 1989 ). The range is Dark Blue ~ 100 to Brown ~ 300 Watts/m2 Right panel : WISER OLR for 1989 from the model simulation. The range is Dark Blue ~ 120 to Dark Red/ Purple ~ 300 Watts/m2 Note: Too much convection off the West Coast of Australia Reasonable representation of the Indian monsoonal convection Strong convection around the tropical date line

Comparison of WISER model 1989 annual average OLR ( outgoing long-wave radiation, W/m2, ) with the ERBE satellite data for (1985-1989)

NCAR simulation

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The outer channel flow representation of the NCAR domain

Results from NCAR simulation, for domains of 12km and 36km A typical weather system pdf The Problem: Typical regional climate models do not capture the most extreme events observed. The pdfs are truncated at high end due to: • resolution – cannot resolve the relevant processes; • capacity – do not include the relevant processes; • rarity – cannot be run long enough to sample the tail.

Done et al.

Wiser Expected Overall Outcome.  

The overall aim is to establish how regional scale climatology, such as storm track behaviour, occurrence of blocking anticyclones, severe precipitation and other meso scale processes, in the Western Europe region, and in particular the UK, will change over decadal timescales in a projected global warming scenario (A2).

Provisional objectives and specific outcomes: •  Predicted changes in general precipitation over western Europe and the UK over decadal times scales.

•  Predicted changes in patterns of frontal tracks on decadal time scales and to examine the strength, the frequency and the location of Western Atlantic storm tracks for historical and future simulations, with associated past and future occurrence of blocking in the North Atlantic.

•  Predicted changes in quantity and frequency of severe and hazardous convective rainfall events and the frequency of flash consequential flooding.

•  Under consideration and in collaboration with the Climate Risk Management unit of the Joint Research Centre, the data sets will also be used to drive European and global set-ups of hydrological models to assess possible changes in frequency and geographical distribution of hydrological extremes on European and Global scale.

Summary

Questions please?

Recent examples

Boltby , North Yorkshire

19 June 2005 The spillway failure of the Ulley Dam near Rotherham at the end of June 2007

Boltby rainfall and flash flood

River Rye and Cod Beck with rainfall isohyets, 19 June 2005; 125 mm in 3 hours.

Note the location of Boltby reservoir (shown by black dot) (from Wass et al. , 2008).

Flooding at the temporary campsite at Duncombe Park. Had the storm occurred 24 hours earlier, the site

would have been occupied with 10,000

people in tents attending a biker’s rally.

•

Consequences

The high water level downstream of the Ulley reservoir, and the threat of the dam failure, resulted in the closure of the M1 motorway for 40 hours, and the evacuation of 1,000 residents from the villages of Catcliffe, Whiston and Treeton.

During the Boltby incident a temporary camp site at Duncombe Park near Helmsley in North Yorkshire was evacuated (Wass et al., 2008). Had the storm occurred 24 hours earlier and the dam failed completely 10,000 people sheltering in tents attending a rally would have occupied the site and been at risk. The flood occurred on rivers which had not experienced serious flooding in living memory.

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