Harvest Forecast Research Articles

WEB-BASED HARVEST FORECAST OF CAULIFLOWER FOR THE AGRI -FOOD-CHAIN

A web-based Danish ICT system to forecast the harvest time of cauliflower is presented. The system combines a deterministic growth model of cauliflower with an online weather database and an online production database for fruit and vegetable growers, which is still under development. The system enables growers to retrieve an updated harvest forecast of a particular planting from the field with an advanced mobile telephone. From the office pc the grower can follow the growth of all cauliflower crops to obtain an early warning if the growth differs from the scheduled, thus distorting the delivery plan. The system also gives wholesale dealers access to aggregated results from their associated growers, showing the expected number of delivered curds from each grower each week.

A New Approach to Consider the Pollen Variable in Forecasting Yield Models1

Methods for forecasting harvest yields have been improved considerably in the last 20 years with the development of new data survey (remote sensing) and statistical techniques. One of these methods, based on pollen release in the atmosphere, is especially important for anemophilous species such as olive. The aim of the present work is to use a different approach to forecast the olive harvest by considering the pollen variable as “endogenous” because it is involved in the consequential processes from the formation of pollen to fruiting, the complex of which determines, more or less, the final production. Unlike models built upon a single equation (multiple linear regression analysis), the proposed estimate, based on an incomplete system of equations, recovers the consistency associated with the inference of parameters while avoiding the errors of “over-estimation.” The study, based on 17 years of data considers the quantity of olive pollen monitored and the relative annual olive production in addition to climatic, agronomic, and pathological variables associated with production. The harvest forecast provides the possibility for planning and optimizing the various stages of olive production from cultivation to distribution, including sound management of the olive supply.

A timber harvesting model for Austria

Between 1981 and 1985 the Austrian National Forest Inventory (ANF) established a set of 5500 clusters, each with four permanent plots covering all Austrian forests. After the first remeasurement between 1986 and 1990 models were developed to predict tree growth, mortality and the behavior of forest owners in harvesting timber. A set of logistic equations describes the probability for a given stand to exhibit intermediate harvesting, single-tree selection or final clear cutting. Independent variables were either continuous or categorical, describing: (i) regional units such as provinces, (ii) types of ownership (groups of ownership sizes), (iii) site factors (elevation and slope), and (iv) stand characteristics (species mixture, density, mean diameter). Timber removals on the plots are recorded by five relative diameter at breast height (dbh)-classes. Removal percentages differ by elevation, harvesting categories, and tree species groups. Timber harvest forecasts and their spatial arrangement over Austria in the following four 5-year periods were made available to the public using computer software. In 1997 data of the second inventory remeasurements were available and thus the forecasts for this period could be evaluated. When forecast units are large enough, deviations from the model are either small or can be explained by a different timber market scenario and/or a general socio-economical scenario.

Are Harvest Forecasts News? USDA Announcements and Futures Market Reactions

AbstractFutures market price data for corn and soybeans are used to examine reactions to U.S. Department of Agriculture harvest forecasts. These forecasts are widely known and reasonably accurate, so failure to find significant reaction would indicate that the USDA did not contribute additional news relative to information already possessed by traders. Various t‐tests, F‐tests, and nonparametric chi‐square tests indicate rejection of the null hypothesis of no significant difference between means of absolute values or variances of changes in closing prices on days following a USDA announcement and other days. Thus, the data indicate that significant information is contained in the forecasts.

Practical Meteorology

THE Meteorological Committee has issued its first report, for the year ended March 31, 1906. In compliance with the desire expressed by H.M. Treasury, the work of the office proceeds generally on the lines hitherto followed, and the committee record “their appreciation of the services rendered in the administration of the office by Sir R. Strachey, the chairman of the council for twenty- two years,” and by other members. An important addition has been made by participation in the investigation of the upper air by means of kites. It is also proposed, if practicable, to make use of unmanned balloons, and to render the service more effective by cooperating with the representatives of other bodies concerned in the work. Among some of the useful researches initiated or completed during the past year may be mentioned (1) the study of the trajectories of air in travelling storms, embodied in an official publication entitled “The Life-history of Surface Air Currents”; (2) re-determination of the velocity equivalents of the Beaufort scale of wind force; (3) connection between the yield of wheat in eastern England and the rainfall of the previous autumn; and (4) possible relationship between exceptional strength of the south-east trade wind at St. Helena and exceptional rainfall in England. Reference to these investigations has already been made in our columns. We note that the payment hitherto made to Dr. Buchan, as inspector of stations in Scotland, is to be continued for the time being in consideration of his important work in connection with the discussion of the results obtained at the Ben Nevis observatories. The corn-plete or partial success of the weather predictions was very satisfactory during the year in question, e.g. harvest forecasts, 89 per cent.; forecasts appearing in morning newspapers, 88 per cent.; in both cases the best results were obtained in eastern and southern England. The number of torrn-varning telegrams justified by subsequent gales or strong winds was 88.4 per cent. The committee points out that the service of storm warnings, which is extremely difficult on account of meteorological reasons, is aggravated by the frequent impossibility of getting telegrams delivered on the day of issue when dispatched in the evening or on Sundays, and it proposes to give this serious matter lurther consideration in the current year. The ordinary work of the marine and land branches has been much augmented by the reduction and tabulation of the observations of the National Antarctic Expedition and of auxiliary observations made in connection therewith, both at sea and on land, south of 30° S. latitude.