Bluetongue Advisory No June 2017

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Laurence Tucker
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1 Bluetongue Advisory - risk of airborne introduction to UK from the near-continent ummary: Period June to 1. ummary Disease (Completed by APHA): France has continued to report a small number of outbreaks since our last report, but no further cases detected along the North coast. No other countries have reported BTV-8. idge activity (Completed by The Pirbright Institute): The vector season began on the 12th April. idge activity is high at all eight sites monitored for their abundance. While the expected high temperatures are likely to lead to a greater efficiency of BTV transmission, this is related largely to reduction in the time taken for infection and dissemination of the virus to occur in the midge. urvival of adult midges is generally reduced at higher temperatures (>30 C) due to desiccation, particularly in conditions of low humidity and in extended dry periods. Little is known regarding the degree to which midges avoid these conditions through selection of cooler resting places. 1

2 eteorology/modelling (Completed by the et Office): Over the last fortnight there have been several occasions where air trajectories have passed over the UK, at both sunset and sunrise, affecting southern counties. Temperature observations at 2 m above ground level show that temperatures have been rising over the past two weeks. The means of the maximum temperatures have been above 15 ºC across the region over the past two weeks (with most areas experiencing high temperatures > 20 ºC). ean temperatures have been above 12 ºC with many areas above 15 ºC. Temperatures across northern France and the south of England are expected to remain high for the rest of this week, although cooling slightly towards the weekend. Winds are predicted to be light and south-westerly by the weekend. 2. Overall risk level Negligible.Very low/ Low /edium/high/very High. 3. Contact details Please send any enquiries to iadm@apha.gsi.gov.uk. Information contained in this advisory was compiled from contributions from those listed below. Animal & Plant Health Agency Helen Roberts Ruth oir et Office arah illington Frances Beckett The Pirbright Institute imon Gubbins Anthony Wilson imon Carpenter 2

3 OURCE IN FRANCE Bluetongue Advisory No Detailed analysis of dispersion modelling output (see appendix for details on the modelling) ource 1 Brittany, north-west France 2 Normandy, northcentral France 3 Picardie, north-east France Date unrise () or unset () Assessment for tracer () or midge () dispersion* 3,,,,,,,,,, Area at risk Hampshire, Dorset, West ussex, East ussex, IoW, Hampshire, Dorset, IoW, Devon, Dorset Devon, Dorset Devon Devon, Dorset Hampshire, Dorset, IoW, East ussex, West ussex, Kent, Hampshire, IoW, East ussex, West ussex, Hampshire, West ussex, East ussex, Kent West ussex, East ussex, Kent Hampshire, East ussex, West ussex, IoW Hampshire, Dorset, West ussex, East ussex, IoW Hampshire, Dorset, West ussex, IoW Hampshire, Dorset, IoW East ussex, West ussex, Kent Devon, Cornwall,, Cornwall Hampshire, Dorset, East ussex, West ussex, IoW, Kent, East ussex, West ussex Essex, uffolk, East ussex, Kent East ussex, Kent East ussex, East ussex, Kent Devon, Dorset, East ussex, West ussex, IoW, * NAE dispersion model trajectory types showing where they reach the UK: = Channel Islands, IoW = Isle of Wight = tandard modelled trajectories; these represent the movement of an air mass and gives an indication of the worst case scenario. = idge model trajectories; these take into account the seasonal effect on midge activity, together with the effects of temperature, wind speed, relative humidity and precipitation, both at take-off and en route and gives an indication of the most likely scenario.

4 urface temperature observations and forecast 5.1. Overview of temperature observations The observations of temperature at 2 m above ground level are for the past two weeks (06/06/ /06/2017 inclusive). The means of the maximum temperatures have been above 15 ºC across the region over the past two weeks (with most areas experiencing high temperatures > 20 ºC). ean temperatures have been above 12 ºC with many areas above 15 ºC. The mean of the minimum temperatures has been about 15 ºC. 4

UTC Thu 22 June 1200 UTC Fri 23 June 1200 UTC un 25

from the midnight th run of the Global model on the 20

Forecast temperatures remain high over southern

although it will be slightly cooler from Thursday

5 Bluetongue Advisory No Overview of temperature forecast Wed 21 June 1200 UTC Thu 22 June 1200 UTC Fri 23 June 1200 UTC un 25 June 1200 UTC at 24 June 1200 UTC The forecasts are from the midnight th run of the Global model on the 20 June 2017*. Forecast temperatures remain high over southern England and northern France for the coming week, although it will be slightly cooler from Thursday onwards. Winds are expected to be light and dominantly southerly and south-westerly. *Except for the unday forecast which is based on ECWF data. 5

Appendix: odelling overview The et Office s Atmospheric Dispersion odel (NAE) has been run on a twice-daily basis to estimate the likely transport of any infected midges.

6 Appendix: odelling overview The et Office s Atmospheric Dispersion odel (NAE) has been run on a twice-daily basis to estimate the likely transport of any infected midges. NAE is run using two different model configurations using meteorological data with 4 km horizontal spatial resolution. In both configurations modelled particles are released over a 2 hour period at sunrise and over a 3 hour period at sunset to represent the diel periodicity of midge activity. The particles are released from m above ground level. This height is assumed to be above the normal flight boundary layer of midges, where wind speed is greater than midge flight speed, and therefore excludes midges undertaking active local-scale flight. Particles are then dispersed for 12 hours (based on wind-tunnel experiments on the flight duration of midges). The two configurations are: 1. tandard run: This assumes a standard release of particles (an inert tracer) from seven sites on the near continent (see figure below). It represents the movement an air mass and indicates the worst case scenario in terms of the maximum dispersion of air from the sources. 2. idge run: This, for the same sites, takes consideration of the seasonal effect on midge activity, together with the effects of temperature, wind speed and precipitation at take off and the effect of precipitation on route on an hourly basis. It represents the most likely scenario with a representation of the effect on midge activity at take-off and survivability during air-borne dispersion modelled. 6

YEAR 7 REVISION BOOKLET

YEAR 7 REVISION BOOKLET Assessment checklist 1. To be able to define Geography. 2. Give examples of what we study in geography 3. Group what we study into the three major areas of geography 4. To be able