The Climate Impact Report (Updated 25 January 2018) The Immediate Past

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1 As at 25 January 2018 The Climate Impact Report (Updated 25 January 2018) The Iediate Past 7 day period ending: 24-Jan 17-Jan 10-Jan Total Rainfall Marlborough Research Centre() Total Rainfall Rai () Total Rainfall Awapiri() Total Rainfall - Te Rapa () Total Rainfall - Lower Awatere at Glenbrae () Total Rainfall - Wairau at the Narrows () Total Rainfall - Ngaruru at the Wye () Forecaster s Predicted Average Rainfall for the next 7 days() Forecaster s Predicted Average Wind Speed - next 7 days(km/hr) Forecaster's Predicted Average Temperature - next 7 days ( o C) Average Daily Temperature ( o C) cm Soil Temperature (9.00 am) ( o C) Total PEN Evapotranspiration () Predicted Soil M oisture Clay Loams 35% 50% 50% Plant Available M oisture Clay Loams () Percentage DM grown from 1 July versus LTA 125% 124% 122% Pasture Growth Rates for last week - Wairau (kgdm/day) Pasture Growth Rates for last week - Waihopai (kgdm/day) Pasture Growth Rates for last week - Ward (kgdm/day) Predicted Soil M oisture Silt Loams Plant Available M oisture Silt Loams () 33% 43% 43% Growth Heat Units above 10 o C Cumulative Heat Units todate from 1st July LTA Heat Units from 1st of July Period Ending: 21-Jan 14-Jan 07-Jan Rainfall recorded Lower Avon Valley() Rainfall recorded Ward() Rainfall recorded Okaramio() cm Soil Temperature Lower Avon Valley (8.00am) ( o C) cm Soil Temperature Ward (8.00am) ( o C) cm Soil Temperature Okaramio (8.00am) ( o C) Well Data from the Marlborough District Council Web Site Brancott Vineyard Well Hawkesbury Vineyard Well Conders No 2. Well Predicted Growth Rates for next three weeks given forecast Rainfall and Temperature * Weeks Beginning 24-Jan 31-Jan 07-Feb Wairau (kgdm/day) Waihopai (kgdm/day) Ward (kgdm/day) Predicted Pasture Quality (Metabolisable Energy / kg DM) * Period Ending: 24-Jan 17-Jan 10-Jan Perennial Green Grasses and Clovers Perennial Green Grasses (with less 5% clovers) Climate Report Page 1 of 7 25/01/18

2 *The predicted pasture growth rates in the previous table are generated in a simulated computer model in which the extent to which pasture grows is governed by the long-term averages for temperature and soil moisture. The figures quoted are representative of what should grow if the LTA s are achieved. It is not the amount of pasture available to animals. The ME/kg DM is based on a growing leafy pasture. Stey or dying pastures will have ME values from 1 to 2% lower than the figures quoted. Green clovers do not vary much in ME value. Irrigation Table 1 Estimated Irrigation () required to bring Soil Moisture up to 80% of Field Capacity for next week Takes into account an Irrigation Efficiency of 75% water applied. Wairau 69 Lower Avon Valley 27 Ward 42 Table 2 Table 1 looks out to the next 7 days and takes into account any rain forecast in that period from the long range forecast. Estimated water need (litres/vine) required for this past week was: lts/vine *hours/vine #lts. next week 2,300 vines/ha ,500 vines/ha ,650 vines/ha ,900 vines/ha ,100 vines/ha ,300 vines/ha * This assumes a dripper application of 8 litres per hour # Takes into account the expected rain The above calculation is formulated by subtracting the evaporation from the amount of rainfall for the week. It assumes a status quo soil moisture situation. The irrigation is on a per vine requirement and assumes that the area dampened by the irrigation beneath the vine will be cone shaped. The aim of the irrigation is not to dampen the soil between rows or vines, but moisture applied will move sideways and downwards. The amount per vine is formulated by multiplying last week s ET by the vine crop factor for the month times the row and plant spacings. It assumes that the vines are on a clay loam. The amount per vine will vary according to soil type. The irrigation suggested for the next week takes into account the expected rainfall. At times the rainfall will exceed the irrigation requirement and as a consequence no irrigation will be recoended. The table above is a generalisation of requirements and will vary between farm and districts according to rainfall and current soil moisture. Table 3 Date Marlb Sound The Iediate Forecast Rain () %P Wairau Plain %P Awatere %P East Coast %P Thu nil - 0% nil - 0% % % Fri % % % % Sat % % % % Sun % % nil - 0% nil - 0% Mon % % % nil - 0% Tue nil - 0% nil - 0% nil - 0% nil - 0% Wed % % % % WEEK % % % % Rain Days 5 57% 5 57% 5 57% 4 46% Thu % % % % Fri % % % % Sat % % % % Sun % % % % Mon % % % % Tue % % % % Wed % % % % WEEK % % % % Rain Days 7 80% 7 80% 7 80% 7 80% Climate Report Page 2 of 7 25/01/18

3 Table 4 Temperature Growing Heat Possible Chill Wind Date Minimum Maximum Ave Temp Degr Day Units Frost Units <7 o C Chill o Thu Fri Sat Sun Mon Tue Wed WEEK Thu Fri Sat Sun Mon Tue Wed WEEK Table 5 Date Wind Direction Airflow km/hr Condition Ave Spray Forecast Thu NE Mainly fine Fri SE S >SE Some showers possible Sat SE E ESE spray Mainly fine Sun VB SE Mainly fine Mon SE> NE N Becoming fine Tue NNW N Mainly fine Wed N Cloud develops, showers in west WEEK 1 Range/Average Thu NNE > N NNW Rain and showers Fri NW > W > S Showers clearing Sat WNW Mainly fine Sun SW S Showers clearing Mon WNW Mainly fine Tue W Mainly fine Wed WNW spray Fine WEEK 2 Range/Average Table 6 Regional Marlborough Average rain No. Raindays % Probability Week % Week % These pages are a compilation of data derived from NIWA, Metscape, Accu and Blue Skies. NIWA and MetService Outlooks The latest climate outlooks are available on the NIWA and MetService websites. Their web addresses are: How to Read the Graphs Below All of the graphs below contain three lines or bars of data; the Long Term Average (LTA), last season (2016/17) and this current season (2017/18). If the current season line or bar is above the LTA, then we are better than normal and if the line or bar is below the LTA then we are below normal. Climate Report Page 3 of 7 25/01/18

4 Rainfall and Temperature Graph 1: Cumulative Weekly Rainfall Graph 1 below shows the rainfall to date compared with the last season and the long term median from Cumulative Rainfall - Marlborough Research Centre (Current Season vs LTA) During September to late April, a minimum of 25 of rain each week is needed to sustain even moderate amounts of pasture growth. The days between 10 or greater falls are also a critical factor Last season LTA Cumulative Current Season Graph 2: Monthly Rainfall Wairau Plains For the three graphs below, the rainfall for the current month has been updated to the end of month using the 14-day forecast and the LTA. This means that they currently show the position of rainfall received to date plus forecast rain over the next 14 days plus the effect of receiving LTA for the rest of the month. They will be updated each week Monthly Rainfall as recorded at the Marlborough Research Centre Nov Dec Jan Graph 3: Monthly Rainfall Lower Avon Valley 2016/ /18 Average Lower Avon Valley - Monthly Rainfall Nov Dec Jan 2016/ /18 LTA Climate Report Page 4 of 7 25/01/18

5 Temperature at 9.00am Graph 4: Monthly Rainfall Ward Monthly Rainfall - Ward Nov Dec Jan 2016/ /18 Average 1992/2016 Graph 5: Mean Daily Temperature Mean Daily Temperature Averaged weekly When the Mean Day Temperature rises above 15 o C, even though the improved pasture may seem leafy and green; the quality is likely to be at least 1 Mega Joule of Metabolizable Energy lower Median 2016/ /18 Graph 5 above shows the mean daily temperature averaged on a weekly basis compared with last year and the long-term median from Soil moisture Graph 6: Clay Loams with a moisture holding capacity of Hill Country Soil Moisture Based Clay Loam Field Capacity = 75 Median 1990/2016 Bottom 4 Seasons 2016/ /18 Climate Report Page 5 of 7 25/01/18 Graph 6 depicts the moisture levels on a typical Marlborough Clay Loam Hill Country site. The Clay Loam has a water holding capacity of 75. In this soil the growth in pasture slows at 50% soil moisture and Wilt Point is reached at 25% soil moisture. Wilt Point is when pasture dies. Each data point on the graph represents one week. A heavy rainfall on one day of the week may not be enough to lift that week s data as much as assumed. The brown dotted line represents the trend of the worst 4 years since 1991/92.

6 01-Jan 15-Jan 29-Jan 12-Feb 26-Feb 11-Mar 25-Mar 08-Apr 22-Apr 06-May 20-May 03-Jun 17-Jun 01-Jul 15-Jul 29-Jul 12-Aug 26-Aug 09-Sep 23-Sep 07-Oct 21-Oct 04-Nov 18-Nov 02-Dec 16-Dec 30-Dec % Degrees 9.00am Graph 7: Silt Loams with a moisture holding capacity of Hill Country Soil Moisture Based Silt Loam Field Capacity = 105 The same criteria apply to Graph 7 as to Graph six that is pasture growth slows once 50% soil moisture is reached and ceases at 25% soil moisture. Because of the different soil type and water holding capacity the loams display different moisture holding characteristics compared to a clay soil The brown dotted line represents the trend of the worst 4 years since 1991/ o C Soil Temperature Graph 8 below compares this season s soil temperature against the long-term average and last year. Graph 8: 10 o C Soil Temperature Median 1990/2016 Bottom 4 seasons 2016/ /18 Weekly Soil Temperature 10 centimetres Median 1990/ / /18 Soil moisture at Marlborough Research Centre Soil Temperature has its major effect on pasture growth when it drops below 10 0 C. Below this temperature grasses have a much slower growth rate. Below 7 0 C legume growth virtually stops. Soil temperature varies throughout the day by up to 4 to 6 degrees. This means in winter it can be warm enough for small periods of growth. At a deeper depth the soil tends to be much warmer. Graph 9: Mean Soil Moisture Mean Soil Moisture (5-35cm) from Marlborough Research Centre LTA 2002/16 20 % Percentile The graph to the left shows the Mean Soil Moisture recorded at the Marlborough Research Centre for the Long Term Average ( ), last year and up until yesterday for the current year. It is important to note how quickly it can decline in the first few days after rain. The blue dotted line represents the values of the worst two seasons since Climate Report Page 6 of 7 25/01/18

7 Daily Megajoules/m2 Radiation Graph 10 Radiation Radiation Radiation has an important affect both on evapotranspiration and photosynthesis for plant growth. The higher the radiation level, the greater the ET and plant growth. It is measured in mega joules per metre 2 per day For irrigators using PAN Evaporation, that is an open pan then in general solar radiation is not completely taken into account. LTA / /18 Disclaimer: The information contained in this report prepared for you is research from a variety of sources. Any subsequent action taken or not taken in reliance upon the accuracy of such information supplied is entirely at the responsibility of the user. Ian Blair or the Marlborough District Council shall not be liable for any act, matter or thing, or any accident, loss or damage arising out of or suffered as a result of the use or misuse of such information or any action taken or not taken in reliance upon the validity of such information. Professional advice is recoended for all strategic management decisions needing to be made. A more substantive report, which looks at climate and pasture growth over the next two four weeks, is available on subscription from Ian Blair. For Subscription Information: Please contact Ian Blair, Climate Matters Blenheim, Ph , ieblair@xtra.co.nz. Climate Report Page 7 of 7 25/01/18