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Sunflowers and Climate Change 1 SUMMARY Global temperatures have been rising over the past 25 years by approximately 0.2°C per decade and this has been attributed to an increase in greenhouse gas emissions. The main sources of these gases and aerosols are burning of fossil fuels for energy supply, transport and industry, with an increasing amount coming from residential and commercial, forestry and agriculture. Central England temperatures have seen a 1ºC rise during the twentieth century, whilst the occurrence of hot summer days (>25ºC) almost doubled during the first half of the 20th century. The UK Climate Impacts Programme (UKCIP) was set up by Defra in 1997 to provide a research framework for the integrated assessment of climate change impacts in the UK. An updated set of climate change scenarios for the UK were produced in 2002 and it is these that have been used in this report. The principle factor determining the rate of physiological development in sunflower is the accumulated air temperature (mean daily air temperature over a 6°C). The projections from UKCIP02 data indicate that the area suitable for sunflower production will increase to approximately 79% of the land area of England by 2050. There will be a substantial increase in the number of varieties that will be suitable for use in the UK. Rainfall levels will decrease but this will suit the drought tolerant nature of sunflowers. Diseases currently experienced such as sclerotinia and verticillium wilt may become more important and botrytis less important in future. Phomopsis and phoma are also likely to become more prevalent. 2 INTRODUCTION The climate of the British Isles and the world is already changing. According to the latest and fourth assessment (4AR) of the International Panel on Climate Change (IPCC) ‘warming of the climate system is unequivocal, as in now evident from observations in global average air and ocean temperatures, widespread melting of snow and ice, and rising global temperatures’ (IPCC, 2007, 1). The global mean average temperature has increased 0.74ºC (+/-0.19 ºC) between 1906 to 2005, and over the past 25 years has been rising at about 0.2 ºC per decade (+/-0.05 ºC) (IPCC, 2007, Jenkins et al., 2007). Furthermore, 11 of the last 12 years (1995 to 2006) rank among twelve of the warmest in the instrumental record of global surface temperature since 1850. Rising global sea levels are also consistent with global warming- global sea level has been increasing at an average rate of 1.8 mm/yr since 1961 and at 3.1 mm /yr (+/-0.7mm /yr) since 1993 (IPCC 2007). Other evidence of global climate change include the reduction in the extent of sea ice, with satellite studies showing the average annual Arctic sea ice extent decreasing by 2.7% per decade (IPCC, 2007). 2.1 Drivers of Climate Change Climate change arises from variations in the energy balance of the earth. The earth receives its energy from the sun in the form of short wave radiation. This energy passes relatively easily through the atmosphere and is absorbed by the earth and re-emitted as long wave energy. Some of this long wave energy escapes out to space, whilst some is trapped by greenhouse gases. These gases, keep our earth’s temperature 30 ºC warmer than it otherwise would be. Both changes to the amount of solar radiation entering the atmospheric system and the amount of greenhouse gases in the atmosphere can cause climate change. The causes of climatic change are natural. For example, changes in solar activity, the orbit of the earth around the sun or natural oscillations within the climate system such as the North Atlantic Oscillation or El Nino Southern Oscillation (ENSO). Volcanic eruptions are also an important driver of natural climate change. These changes have occurred throughout the earth’s history, and have resulted in cooler and warmer periods such as the Little Ice Age and the Medieval Warm Period. Anthropogenic or human induced changes on the climate arise from 1 activities that increase the concentrations of greenhouse gases and aerosols in the earth’s atmosphere, preventing long wave radiation from escaping to space and thereby cause anthropogenic ‘global warming’. The current observed warming of the earth’s global climate is happening at a much faster rate than previously experienced in history. The recent global climate models show that the current warming trend cannot be explained by natural variations alone and that for the models to agree with current observations, anthropogenic effects must be included (Hulme et al., 2002, IPCC 2007, Jenkins et al., 2007). It is very likely (>90% probability) that the main cause of the recent observed global climate changes is an increase in anthropogenic Greenhouse Gas emissions (IPCC, 2007). The Fourth Assessment Report (4AR) from the IPCC states that between 1970 and 2004 there has been a 70% increase in anthropogenic Greenhouse Gases. The main sources of these gases and aerosols are burning of fossil fuels for energy supply, transport and industry. Residential and commercial, forestry and agriculture have also increased as a source of Greenhouse Gases, but at a much slower rate. Different Greenhouse Gases and aerosols have different radiative properties and lifetimes in the atmosphere and therefore varying warming effects. The most important anthropogenic Greenhouse Gas is Carbon Dioxide, which is very long lived (100 year life span) and is mainly a consequence of burning fossil fuels and to a lesser extent land use (e.g. deforestation). Carbon Dioxide concentrations have increased by 80% between 1970 and 2004. Pre industrial levels of Carbon Dioxide were 280 ppm but by 2005 reached a level of 379 ppm (IPCC 2007). Methane, nitrous oxide and halocarbons are also important and long lived Greenhouse Gases. The main anthropogenic source of methane is agriculture and land use whilst nitrous oxide is mainly from agriculture. Methane has increased from 715 ppb pre industrial levels to 1774 ppb in 2005 (4AR, IPCC 2007). Nitrous oxide has increased from 270 ppb to 319 ppb in 2005 (4AR, IPCC 2007). Agriculture is therefore affected by and contributing to climate change. 2.2 Observed Climate Change We do not have to look back very far in our recent climate history to understand the impact of climate change on agriculture and our society as a whole in the UK. For example, the hot summer of 2003, the floods of autumn 2000 and summer 2007. The UK climate has changed over the 20th Century, which is consistent with the warming in global climate (Hulme et al., 2002). Some of the headline messages for the UK published by UKCIP are summarised in the Table below. Some of the main points are as follows: • Central England temperatures have seen a 1ºC rise during the twentieth century, whilst the occurrence of hot summer days (>25ºC) almost doubled during the first half of the 20th century (IPCC 2007). August 2003 saw the hottest maximum temperature ever recorded in the UK, 38.5 ºC in Faversham, Kent. • Air frosts have been declining in frequency • Predictions suggest that the UK will continue to get warmer with summers being hotter and drier • Winters have been getting wetter and there is a larger proportion of heavy rainfall events throughout the year (Hulme et al., 2000). • Winters will continue to get milder and wetter. 2 Table 1 Summary of UK Predicted and Observed Climate Changes (source: Hulme et al., 2002, Jenkins et al., 2007, Perry 2006). Climate variable UK Observations (Jenkins et al 2007, Hulme et al 2002 and Perry 2006) UK Predictions (UKCIP 02) Average Annual Temperature Regions of the UK have seen a significant rise between 0.47 and 1.18 ºC between 1916 and 2006. Since 1961 and 2006 all regions have seen a significant increase between 1.05 and 1.67 ºC. By 2040 an increase of 0.5 and 1 ºC and by 2100 an increase of 1 and 5 ºC. (High confidence) Average Summer Temperatures Increased between 0.55 and 1.02 ºC between 1916 and 2006 and between 1.24 and 1.9 ºC since 1961 By 2040 expected to increase by 0.5 to 2 ºC depending on region. By 2100 rises between 1 and 6 ºC expected depending on region and scenario (High confidence). Summer Heat waves Average duration of summer heat waves has increased in all regions between 4 and 16 days since 1961 (UKCIP 02) Number of very hot days expected to increase, with high temperatures similar to August 2003 or July 2006 (>3 ºC above average) predicted to be more frequent under low emissions scenario (medium confidence) Average Winter Temperatures Increased significantly since 1961 by between 1.22 and 2.02 ºC across the UK. Expected to increase between 0.5 and 1 ºC by 2040 and between 1 and 4 by 2100 (high confidence) Temperature extremes Warming will be greater in SE compared to NW (high confidence) and greater for summer and autumn than winter and spring (Medium confidence). Number of very hot days increases, especially in Summer and Autumn (high confidence) Heating Degree Days Heating degree days across UK regions have decreased by 12 to 18% between 1961 and 2006. Decrease across the UK (high confidence) Air Frost Days of air frost have decreased by between 19 and 28 days across UK regions between 1961 and 2006 Expected to decrease (high confidence) Cooling Degree Days Change between 2.5 and 32.3 days between 1961 and 2006 over the UK Increase everywhere across the UK (high confidence) Thermal Growing Season Increased by up to 30 days since 1900 Season will continue to lengthen, with largest increases in the SE (high confidence) Soil Moisture Content Annual Precipitation Soil moisture contents in summer and autumn are expected to decrease (high confidence) Not changed significantly since records began in 1766 with high inter annual variability; except for 3 Climate variable UK Observations (Jenkins et al 2007, Hulme et al 2002 and Perry 2006) UK Predictions (UKCIP 02) Scotland which has seen an increase by up to 23%. Summer Rainfall Decreased in most regions by up to 16.7% - although not all regions see a decrease or a significant trend. Small decrease in contribution of heavy rainfall days for some region by up to 1.8 days but not significant. By 2100, up to 50% reduction depending on scenario and region (medium confidence) Winter Rainfall All regions have shown an increase in winter rainfall since 1961, varying between 11 and 66%. Small increase in the contribution of heavy rainfall days (> 1mm) by between 1.4 and 8.6 days, but not significant. By 2100, up to 30% increase depending on scenario and region (high confidence) i.e. wetter winters Precipitation Intensity Increases in winter (high confidence) Snowfall Number of days with >50% snow cover has decreased by between 3.5 and 18.6 days between 1961/2 and 2004/5 (Perry, 2006) Snowfall amounts expected to decrease (high confidence) and many regions will have no snow for multiple winters (low confidence) Storminess Severe wind storms around the UK have become more frequent in last few decades, although not as stormy as 1920’s. Windiest periods coincide with positive NAO index. Winter depressions confidence) Relative Humidity Annual relative humidity values across the UK have seen a decrease between 0.8 and 4.3% between 1961 and 2006. Specific humidity increases throughout the year (high confidence). Relative humidity decreases in summer (medium confidence) Sea Level Pressure Annual changes in sea level pressure have been small and not significant between 1961 and 2006 across the UK. Sea Surface Temperatures Increased over the last 30 years by 0.7 ºC around UK Sea surface temperatures expected to increase but not as rapidly as air temperatures (high confidence) Sea Level Increase of 1mm/yr in 20 Century, corrected for land movement and even higher in the last few decades. th Extreme sea levels are expected to occur more frequently and by 2100 storm surge events could occur 20 times more for some coastal locations (medium confidence) become more frequent (low Significance level refers to 95% significance level in the table. Period trend analyses is conducted on is 1961 to 2006 unless otherwise stated. 4 3 BACKGROUND TO CLIMATE CHANGE SCENARIOS Climate change scenarios are plausible descriptions of how things may change in the future (Hulme et al., 2002). The UK Climate Impacts Programme (UKCIP) was set up by Defra in 1997 to provide a research framework for the integrated assessment of climate change impacts in the UK (Holman et al., 2007). The first climate change scenarios were released in 1998 (UKCIP98) as documented in Hulme and Jenkins (1998). In 2002, UKCIP published a new set of climate change scenarios for the UK, which were based on the Met office Hadley Centre global climate models, and a Regional Climate Model (RCM) which allowed the projections to be downscaled over Europe to give greater spatial detail at 5km (Hulme et al., 2002). The UKCIP02 scenarios are the most up to date scenarios available to the research community at this time. It was hoped that UKCIP 08 data, the fifth generation of UK climate change scenarios, would be available for this project. However, due to a delay in the release of the data, the now called UKCIP 09 data is not available for this work. The advantage of the UKCIP 09 data over the UKCIP 02 data is the provision of probabilistic climate projections, which provide greater understanding of the uncertainties associated with the modelling outputs. For further information on the UKCIP 09 data, please refer to http://www.ukcip.org.uk/. As a result, this study uses UKCIP02 scenarios. The UKCIP02 scenarios are averaged over 30 year periods centred on the 2020’s, 2050’s, and 2080’s. There are four emission scenarios which take into account variation in demographic, economic and technological driving forces that result in different Greenhouse Gas emissions, as summarised in the Table below. The low, medium-low, medium high and high scenarios are based on the global emission scenarios from the IPCC Special Report on Emission Scenarios (SRES, 2000). The scenarios predict increases of global Greenhouse Gas emissions of between 25-90% (CO2 equivalent), for the period 2000 and 2030. Note that typically the 1961-1990 climate period is used as the comparison baseline for the scenario predictions and that for the 2020s scenarios, predicted climate changes are similar for all scenarios because they are linked to our past emissions to which we are committed due to inertia in the climate system (Hulme et al., 2002). Table 2 Summary of the UKCIP 02 Emission Scenarios (adapted from UKCIP 2008, Glynn 2008) SRES UKCIP02 Description A1F1 High Emission s Rapid economic growth, global population peak mid century and then declines, rapid introduction of new technologies but continued reliance on fossil fuels. 3.9 810 A2 MediumHigh Emission s A heterogeneous world with high population growth. Regional focus to economic development and local identity remains strong. Technological change is slower and more fragmented than other scenarios. 3.3 562 B2 Medium Low emissions An intermediate population and economic growth rate with local solutions to economic, social and environmental sustainability. Technological change is less rapid and less diverse than in high and low scenario. 2.3 562 B1 Low emissions A convergent world with regional and global solutions to economic, social and environmental sustainability. Global population as in high emissions scenario but with rapid changes in economic structures towards a service and 2.0 525 Mean Global Temperature (C) in 2080s 5 Atmospheric CO2 Concentration (ppm) in 2080s information economy and introduction to clean and resource efficient technologies There are a number of uncertainties associated with future climate change scenarios and specifically the UKCIP02 predictions. These uncertainties must be considered when assessing climate change impacts and risks (Arkell et al., 2007, Hulme et al., 2002). The main uncertainties associated with the UKCIP02 predictions are summarised below. Table 3 Uncertainties associated with climate change scenarios (based on UKCIP (2008b) Uncertainty Description Emissions Emissions used in the climate models are estimated and depend on future population and world technological development. A range of emissions from low to high is provided to mitigate this uncertainty. Model Although the models used to generate the climate change scenarios are the best available in the world, they do not allow a full quantitative description of climate sensitivity and not all climate feedbacks are fully understood and represented in the models (e.g. North Atlantic Drift). Various models handle different climate processes differently and is the reason why UKCIP 08 will use ensemble predictions to quantify this uncertainty. Natural climatic variability The natural variability in the climate system cannot yet be modelled, and neither can the climate feedbacks. This means that the uncertainty in extreme events is greater than seasonal or annual means, as the uncertainty in the longer term trends is less. Impacts There is also some uncertainty in the impacts that climate change will have on different sectors- based on current understanding and do not account for future policies. UKCIP 02 scenarios provide useful information on long term average climate changes, but do not give much indication for extreme events. Vulnerability to climate change is often determined by the frequency and magnitude of extreme events. 4 DATA 4.1 1971-2000 Climatology To understand the current climate for growing sunflowers in the UK, data from the Met Office 1971-2000 climatology and the Met Office Agricultural Land Classification (ALC) 1971-2000 climatology has been used. The 1971-2000 Met Office climatological database is the most recent official 30 year climatology available. The following parameters, which are important for sunflower growing in the UK, have been summarised. • Mean monthly 30 cm soil temperatures for April and May, to estimate soil temperatures on 1st May (ALC 1 km database) • Mean accumulated air temperatures above 6 ºC. This parameter is estimated from the 1971-2000 mean maximum and minimum temperatures (Met Office 5 km database). • Mean monthly rainfall rate (mm/ month) (ALC 1km database). • Mean monthly number of rain days (>0.2 mm per day) and wet days (>1.0 mm per day) (Met Office 5 km database). 4.2 Climate Change Data The UKCIP 02 medium-high scenarios are used to represent the future climate of the UK in the 2020’s and 2050’s. The UKCIP parameters used in the study were as follows: 6 Accumulated temperatures above 6 ºC, estimated from the UKCIP02 mean temperatures at 5km resolution • Mean monthly rainfall rate (mm /month) at 5 km resolution Unfortunately, there are no soil temperatures available in the UKCIP02 database, and there are no known methods for estimating soil temperatures from the available parameters. Furthermore, wet and rain days are not available parameters in the scenarios. • 5 RESULTS A review of UK sunflower production completed in 1998 (Cook et al.,, 1998) identified the parameters for successful sunflower production. Soil type, fertility and lack of water were unlikely to be limiting. There were two major constraints on production: 1. The period available for production determined by the earliest date on which sowing was practicable (minimum soil temperature) 2. the latest date at which maturity is completed and harvesting can no longer be delayed (accumulated air temperature) 5.1 Soil temperature Sunflowers are drilled when soil temperatures at 5 cm are 6-8 °C, which usually occurs between mid-April and mid-May in the UK. This is approximately equivalent to the soil temperature of 10 °C at 30 cm. Temperatures at 30 cm give a greater degree of consistency than at the soil surface. The mean soil temperature at 30 cm for the 1st May, was derived from the Met Office Agricultural Land Classification dataset at a resolution of 1 km. As only monthly values are available, the mean soil temperature on the 1st May was estimated by taking the mean of April and May soil temperatures. Soil temperatures in excess of 10 °C are found in a broad area to the south of a line from the Wash to the Severn estuary. Values greater than 10°C can also be found in small areas along the Welsh coast, parts of Shropshire and around the Wirral (Figure 1). No soil temperatures are available in the UKCIP02 database but it could be concluded that with the rise in air temperature that soil temperatures would rise similarly (Harrison and Butterfield, 1996). Sunflowers would then be able to be sown earlier and on a greater area than currently suitable. 7 Figure 1 Mean soil temperature at 30 cm on 1 May (1971-2000 data). 5.2 Accumulated air temperature Accumulated air temperature (mean daily air temperature over a base value) is the principal factor determining the rate of physiological development in sunflower. The base value for sunflower is 6 °C (Hutley-Bull, unpublished) the same as for maize. For both the observed 1971-2000 climatology and the UKCIP 02 climate projections, the mean accumulated air temperatures (measured in Degree Celsius Days above 6 ºC), were estimated from the gridded mean temperatures. For the UKCIP 02 scenarios, the mean monthly temperatures were provided. For the Met Office 1971-2000 climatology, mean monthly temperatures were estimated from mean of the minimum and maximum monthly temperatures. The relationship between mean monthly temperatures and daily mean accumulated temperatures above a base of 6 ºC was derived from observed daily data. Eight meteorological stations, representative of geographically diverse areas of the UK, were chosen to derive the regression relationship. The monthly accumulated temperatures above 6ºC were calculated for each station, for the period 1980 to 1995. The mean monthly temperatures were calculated from the 1971-2000 air temperatures for each of the stations. A regression analysis between the monthly accumulated temperatures and the monthly temperatures was performed for April to October, since these are the months which are important for growing sunflowers. A strong relationship with a R2 of 0.995 was found. The relationship, as stated in equation 1, was subsequently applied to the 5km gridded mean monthly temperatures in the 1971-2000 and UKCIP 2020 and 2050 scenarios. Act = (0.9363 * Tave)- 4.9324) * No. of Days in Month Where; Act = Monthly Mean accumulated temperature above 6C (°C days) 8 (eq 1) Tave= Monthly mean temperature A total of 1400 ºC days heat input is the minimum needed to produce a crop of semi-dwarf sunflower defined by CETIOM as très précoce which are the type of sunflower grown in the UK. In order to achieve a total of 1400 ºC days during most years, the seasonal mean value would have to be higher. From statistical tables it is calculated that to exceed the thermal sum threshold during nine years out of ten, the mean value would have to be 1.282 standard deviations greater. The standard deviation of the seasonal totals from the Met Office sites was 100 ºC days. This gives a required mean total of 1400 + 1.282 (100) = 1528 °C days. Three seasonal periods were assessed (a) May to October (b) May to September (c) April to September. The seasonal values were calculated by summing the monthly mean accumulated temperatures above 6 ºC (°C days) for the relevant months. These scenarios must be considered in relation to the suitability of sunflowers within local rotations and cropping patterns, where low soil temperatures discourage early drilling and where severe frosts in October make harvesting impracticable. Currently sunflowers are drilled early May when soil temperatures reach threshold and harvested in early October when mature. Production outside this period can occur but very rarely. The past 2 seasons, 2007 and 2008, have been very poor for sunflower production in the UK due to high rainfall and low temperatures. The area suitable for sunflower production based on accumulated air temperature is shown in Figure 2 and is limited to an area south of a line drawn between the Wash and the Severn and accounts for approximately 22% of England. The UKCIP scenarios for 2020 (Figure 3) and 2050 (Figure 4) indicate sunflowers could be grown successfully, in England, south of the Humber and into north east Yorkshire, accounting for 50% of the area by 2020 and 79% by 2050. With the increase in temperatures the varieties currently grown (semi-dwarf types) would mature earlier bringing harvest forward to September, currently this is rarely achieved (Figure 5) but would be more likely in 2020 and 2050 (Figure 6 and Figure 7). The likely outcome of temperature increases would bring drilling dates forward to April and harvest to September; currently this is not a viable option except for small areas of southern UK (Figure 8). In 2020 the area suited to production becomes more widespread south of the line between the Wash and the Severn (Figure 9). By 2050 the area suited for production is south of the Humber and including NE Yorkshire (Figure 10). It would be likely that the current vary early sunflower varieties would be grown in the northern areas possibly using a later drilling date whilst the increasing temperatures would enable southern UK growers to grow a wider range of early, midseason and possibly late varieties as now grown in France (CETIOM, 2008). Varieties with resistance to disease and different oil profiles will be available to UK growers. Successful harvest of sunflowers could be routine during August and September under the projections for 2020 and 2050. 5.3 Rainfall Sunflower can produce reasonable yields where rainfall is as low as 420 mm per annum and much depends on the seasonal distribution, the crop primarily needing moist conditions for establishment. The crop is most responsive to irrigation as the flower bud forms through to early maturity as the back of the heads turn yellow. CETIOM (2008) advise that 30-100mm of water at this time will be sufficient but this depends soil water reserves and the state of the crop. Too much irrigation can make crops lush and more susceptible to disease. Projections for rainfall (Figure 11, Figure 12 and Figure 13) indicate less rainfall over the UK which would suit the crop more so than current spring crop alternatives. Irrigation may have to be applied at the susceptible growth stages. 9 5.4 Disease implications In 2020 and 2050 sowing date could have moved back into April, temperatures and therefore seedling disease problems will therefore be similar to the current situation. Many soil-borne pathogens are active above specific temperature thresholds, but also require adequate soil moisture (Smith and Gladders, 2009). The main periods of activity can therefore be defined. Sclerotinia’s apothecial activity could extend throughout the year with a 2ºC temperature rise. Whilst higher temperatures are expected to increase disease severity, the more critical factor is likely to be rainfall distribution. Soils must be moist for several days for sclerotia of S. sclerotiorum to germinate and produce apothecia. This must continue for a further period to allow ascospore production and dispersal. However, periods of several weeks without rainfall do not necessarily stop sclerotinia activity, as noted in April 2007 when sclerotia germinated in soil cracks or from moist soil several centimeters below the soil surface (Gladders et al., 2008). Dry soils in summer and high temperatures could inhibit spore production, with temperatures >26ºC also inhibiting ascospore infection (Koch et al., 2006). Under climate change, there may be changes in the strains of S. scleriotiorum that affect crops, if some types are adapted to higher temperature conditions. Rainfall is expected to be less frequent, but be more intense. Infection events are expected to occur, but may be less numerous than at present in summer. Infections that do occur may develop more rapidly. On sunflower the damage caused early in the season may increase, whilst late season infection is decreased by high temperatures. In contrast to sclerotinia being dependent on moist soils and days with rainfall, verticillium wilt is likely to be more damaging when summer temperatures are higher and crops are under moisture stress. Host infection requires moist soils and soil temperatures above 15ºC. Thereafter, the disease has a soil temperature optimum of 24ºC (Schnathorst, 1981) and would be more damaging when rainfall was low. Botrytis has been most damaging when it caused severe head rot on late harvested crops. Under climate change, the adoption of early maturing varieties and completion of harvest during September should reduce the severity of attacks. Again, rainfall distribution will be influential as heavy rain over 2-3 day periods is likely to sufficient for sporulation, infection and lesion development to occur. It appears likely that sclerotinia and verticillium wilt may become more important and botrytis less important in future. As the changing climate will resemble parts of northern and eastern France, other diseases such as Phomopsis and Phoma are likely to become more important. Care must be taken with choice of varieties, crop rotations and avoidance of irrigation at full flower to ensure that future disease risks are managed. 6 CONCLUSIONS • UKCIP projections for 2050 indicate that the area suitable for sunflower production in the UK will increase to approximately 79% of the land area of the UK. • Decreasing rainfall levels will suit the drought tolerant nature of sunflowers. • Diseases currently experienced such as sclerotinia and verticillium wilt may become more important and botrytis less important in future. • Phomopsis and phoma are also likely to become more prevalent in crops. 10 Figure 2 Average Accumulated Temperatures 1971-2000 (B) May to October (6 months) 11 Figure 3 Average Accumulated Temperatures 2050’s Scenario (B) May to October Figure 4 Average Accumulated Temperatures 2050’s Scenario (B) May to October Figure 5 Average Accumulated Temperatures 1971-2000 (A) May to September (5 months) 12 Figure 6 Average Accumulated Temperatures 2020’s Scenario (A) May to September Figure 7 Average Accumulated Temperatures 2050’s Scenario (A) May to September Figure 8 Average Accumulated Temperatures 1971-2000 (C) April to September (6 months) 13 Figure 9 Average Accumulated Temperatures 2020’s Scenario (C) April to September Figure 10 Average Accumulated Temperatures 2050’s Scenario (C) April to September Figure 11 1971- 2000 Figure 12 2020’s Medium-High Scenario 14 Figure 13 2050’s Medium-High Scenario © Crown Copyright 2002. The UKCIP02 Climate Scenario data have been made available by the Department for Environment, Food and Rural Affairs (Defra). Defra accepts no responsibility for any inaccuracies or omissions in the data nor for any loss or damage directly or indirectly caused to any person or body by reason of, or arising out of any use of, this data 7 REFERENCES Arkell, B., Darch, G. and McEntee, P. (Eds). (2007). Preparing for Climate Change in Northern Ireland, SNIFFER, UKCC13. CETIOM (2008) http://www.cetiom.fr/index.php?id=2441 Cook S.K., McCartney H.S., Fletcher B, Hutley-Bull P.D., Barrie I. and Harris D. (1998) The role and position of sunflower in UK Agriculture. Review report to Defra (ST0130), July 1998. Gallani, M. (2007). Chameleon: Changes to Agricultural Management Under Extreme Events – Liklihood of Effects and Opportunities Nationally. Report by the Met Office for Defra, May 2007. Gladders P, Ginsburg D, Smith JA. (2008) Sclerotinia in oilseed rape – a review of the 2007 epidemic. HGCA Project Report No. 433, 44pp. Glynn, S. (2005) Climate change in the Northwest and its impacts: a summary document. Report to the Northwest Climate Group. Harrison, P.A. & Butterfield, R.A. (1996). Effects of climate change on Europe-wide winter wheat and sunflower productivity. Climate Research, 7, 225-241 Holman, IP, Berry PM, Mokrech M, Richards JA, Audsley E, Harrison PA, Rounsvell MDA, Nicholls RJ, Shackley and S, Henriques C (2007) Simulating the effects of future climate and socioeconomic changes in East Anglia and Northwest England: The Regis2 Project. Summary Report. UKCIP, Oxford 2007. Hulme, M., et al.,. (2002). Climate Change Scenarios for the United Kingdom. The UKCIP02 Scientific Report, Tyndall Centre for Climate Change Research, School of Environmental Sciences, University of East Anglia, Norwich, UK, 120 pp. Hulme, M. and Jenkins,G. 1998. Climate Change Scenarios for the UK Scientific Report, UKCIP Technical Report Number 1, Climate Research Unit, Norwich 80pp. 15 IPCC (2007). Climate Change 2007. The Fourth IPCC Assessment Report. Jenkins,G., Perry, M. and Prior, J. (2007). The Climate of the UK and Recent Trends. Met Office Hadley Centre, UK. Koch S, Dunker S, Kleinhenz B, Rohrig M, Tiedemann A von, (2006). A crop loss-related forecasting model for Sclerotinia stem rot in winter oilseed rape. Phytopathology 97, 1186-1194 Perry, M. and Hollis, D. (2005). The generation of monthly gridded datasets for a range of climatic variables over the UK. International Journal of Climatology, 25: 1014- 1054. Perry, M. (2006). A spatial analysis of trends in UK climate since 1914 using gridded datasets. Met Office National Climate Information Centre, Climate Memorandum No 21. Smith, J.A, Gladders, P, (2009). Effects of climate change on soil-borne diseases of oilseed rape. Aspects of Applied Biology 91, Crop Protection in Southern Britain (in press) W.C. Schnathorst, (1981) Life cycle and epidemiology of Verticillium. In: M.E. Mace, A.A. Bell and C.H. Beckman, Editors, Fungal Wilt Disease of Plants, Academic Press, New York (1981), pp. 81–111. UKCIP (2008): http://www,ukcip.org.uk/scenarios/ukcip08 UKCIP (2008b): http://www.ukcip.org.uk/scenarios/guidance/uncertainty.aspx Written by Sarah Cook, ADAS UK Ltd. [email protected] This document was funded through the Defra Innovation Network, led by the University of Warwick (www.warwick.ac.uk/go/climatechange/innovation-network), G B seeds Ltd (www.gbseeds.co.uk) and HGCA (www.hgca.com) . January 2009 For more information visit: http://www.hgca.com/content.output/3308/3308/Crop%20Research/Crop%20Research/Sunflowers.mspx 16