WO2004044618A2

WO2004044618A2 - Floating weather station

Info

Publication number: WO2004044618A2
Application number: PCT/IT2003/000733
Authority: WO
Inventors: Luigi Mariani; Roberto Confalonieri
Original assignee: Universita' Degli Studi Di Milano
Priority date: 2002-11-13
Filing date: 2003-11-12
Publication date: 2004-05-27
Also published as: WO2004044618A3; AU2003288725A1; ITMI20022399A1; AU2003288725A8

Abstract

The present invention relates to a floating weather station, particularly a floating weather station which is able to evaluate the meteorological quantities in shallow basins. More particularly, the present invention relates to a floating weather station (1) for the measurement of meteorological variables in a water basin, which is able to float in a few centimeters of water, comprising a supporting structure (100), floating means (3a, 3b) and meteorological surveying means (A1-A5) connected to said supporting structure, characterized in that said supporting structure comprises a base consisting of at least three legs (2) which are placed radially and symetrically, and a shaft (4) extending upwards from the conjunction point of the legs (2).

Description

"FLOATING WEATHER STATION"

The present invention relates to a floating weather station, particularly to a floating weather station which is able to evaluate the meteorological quantities in shallow basins.

In the agricultural sector, the importance and the need for the accurate measurement of meteorological variables, such as temperature, humidity, radiation and wind speed, variables which are necessary for being able to monitor the meteorological conditions to which crops are exposed is well known. Indeed, these meteorological conditions enormously influence the development and the growth of plant life. Furthermore, said variables also influence the development and the growth of parasites, insects and fungi, which in their turn may negatively affect the development of farming, for example by giving rise to diseases. The meteorological monitoring of the ecosystem is therefore extremely important in order to be able to control and anticipate particular growth situations to which the plants may be exposed, allowing therefore, if necessary, to intervene in the growth of the plants themselves. This need for monitoring is particularly felt in the cultivation of rice. Indeed, the paddy fields are subjected to' particular micrometeorological conditions due, fundamentally to the effect of "thermal draughts" exercised on water, above and below the surface of the same .

The Po plain is one of the most northerly areas of distribution in the world for the cultivation of rice. At these "extreme" latitudes, the submersion of the paddy field and the meteorological variables, in particular in the canopy layer, play a very important role in determining the growth and development of plants. As already mentioned above, also, in the cultivation of rice, another important aspect, reconnectable to the temperature of the surface of the water, is associated with the aquatic stages of development of various species of insects. Indeed, the surface temperature of the water greatly influences development and mortality during these stages, important factors which determine the number of adults . A model able to simulate the vertical thermal gradient in shallow basins, by starting from the temperature measured in the air, for situations in which there is an incomplete cover of the water surface by the vegetation has already been provided. A model of this type has been shown to be useful in paddy fields up until the closure of the canopy, or rather up until when the vegetation completely covers the ground. In order to study the thermal profile in paddy fields for the subsequent period, it is necessary to measure the meteorological variables inside the canopy itself and immediately above it, at assigned distances from the surface.

The problem which lies at the heart of the present invention is therefore that of providing meteorological monitoring equipment able to measure the aforecited meteorological variables as a function of the distance from the water surface, and which therefore allows the positioning of the sensors directly in the midst of the canopy itself, maintaining the system as undisturbed as possible.

This problem is solved by a weather station which is able to float in a few centimetres of water without damaging the vegetation, as described in the attached claims . Further characteristics and advantages of the weather station forming the object of the present invention will mostly arise from the description of an example embodiment, made below as a non-limiting indication, with reference to the following figures: Figure 1 represents a perspective view of the floating weather station according to the present invention;

Figure 2 represents a perspective view of the structure of the anchorage means to the bottom of the water basin of a detail of the station of figure 1.

Figure 3A represents a perspective view of the structure of a telescopic arm of a detail of the station of figure 1;

Figure 3B represents a perspective view of the floating shielding means structure of a detail of the station of figure 1;

Figure 4 represents a top view of a detail of figure 1;

Figure 5 represents a sectional view taken along V-V of the detail of figure 4;

Figure 6 represents a front view of the level indicator device associated with the station of figure 1.

With reference to figure 1, the floating weather station, indicated in its entirety with the numeral 1, comprises a supporting structure 100 with a base consisting of three legs 2 arranged radius-like at angles of approx. 120° to one another and a vertical shaft 4 extending upwards starting from the junction point of the legs 2. First floating means 3a are placed at said junction point of the legs 2 with the shaft . Additional floating means 3b are instead fixed close to the distal end of each leg 2. Preferably, said floating means 3a and 3b consist of a polyeurethane sheet. In a further preferred embodiment of the invention, such floating means have a surface which is capable of reflecting radiation, for example a white surface.

Along at least one leg 2 in proximity to the distal floating means 3b anchorage means 2a are provided for anchoring the floating structure of the weather station 1 to the basin bottom. Thus, the station 1 may undulate vertically following the course of the water level, but may not perform any rotatory movements, which would disturb the vegetation.

Said anchorage means 2a to the bottom of the water basin preferably consist of fixing members 24 to the leg 2 and real anchorage members 25. Particularly, as shown in Fig. 2, said fixing members 24 are formed by a bored body, in the throughole of which the leg 2 is housed, preferably in a sliding manner. The anchorage members 25 are constituted, in the example shown, by a slotted member 26 into which a peg 27 is inserted. On the shaft 4, at a prefixed height, of preferably 10-20 centimetres from the attachment point of the shaft 4 to the structure which holds the floating means 3a, 3b, an arm 6 is positioned. Said arm 6, preferably of a telescopic type, is connected to the shaft 4 through vertical joining means 5 and comprises, at its distal end, meteorological surveying means Al. In the described example, such meteorological surveying means Al will comprise a thermometric sensor 28 and floating shielding means 7. The meteorological surveying means Al are themselves connected to the arm 6 by vertical joining means 6b.

As shown in figure 3A, the arm 6 may comprise several modular units 6a terminating in said vertical joining means 6b, the latter being connected to said floating shielding means 7 through coupling means 7c.

As shown in figure 3B, said floating shielding means 7 have a disk-like shape with a central part 7a curving into a semi-cylinder developing along one diameter of the disk, so as to divide the disk into two flat outer half moon-like parts 7b. Said outer parts 7b comprise floating means on the surface of the water basin. Below the arch defined by the central part 7a of the disk a thermometric sensor 28 is suspended through special supports 29. Said thermometric sensor 28 is fixed in such a manner as to be positioned, in operational conditions, submersed under the surface of the water. More particularly, said thermometric sensor 28 is positioned at a constant depth of approx. 1 cm below the water surface. This is achieved thanks to the presence of said floating means associated with said outer parts 7b and of said vertical joining means5 and 6b. The thermometric sensor 28 is connected to the shaft 4 in such a manner as to be free of the same vertical plane, thus preventing said sensor 28 from being affected by any possible oscillations of the entire structure, for example due to wind or to other factors, which would make it come out of the water. Furthermore, the central arched part 7a allows the circulation of air below the disk in such a manner as to not provoke any overheating below the floating screening means 7 which might influence the correct measuring by the thermometric sensor 28. At a second prefixed height, preferably 30-40 centimetres from the floating surface, an additional arm 8a comes out from the shaft 4. At the distal end of said arm 8a meteorological surveying means A2 are positioned, ^* which will preferably comprise an additional thermometric sensor, and shielding means 9a.

At a third prefixed height, preferably 60-70 centimetres high above the floating surface, an additional arm 8b is connected to the shaft 4 which in turn carries at its distal end meteorological surveying means A3 , themselves also preferably comprising a thermometric. sensor, and shielding means 9b.

Finally, additional meteorological surveying means A4, themselves also preferably comprising a thermometric sensor and shielding means 9c, are placed at the head of the shaft 4, preferably at a height comprised of between 140 and 200 centimetres from the water surface, more preferably at approx. 170 cm. According to one possible embodiment, said shielding means 9c which are placed at the head of the shaft 4 additionally provide coupling means to which are fixed tie beams (not shown) , which connect to the screening means 9a and 9b of the meteorological surveying means A2 and A3, located at the ends of the arms 8a and 8b, placed respectively at the aforesaid prefixed heights from the water surface, and which confer considerable rigidity to the overall structure.

On the shaft 4 are additionally arranged acquisition and memorisation means 11 of the meteorological data, preferably a data logger. Said acquisition and memorisation means 11 of the data will be preferably arranged below the screening means 10, more preferably constituted by a disk. Such screening means 10 will preferably have a radiation reflective surface, for example a white surface. Below said acquisition and memorisation means 11 of the data are preferably envisaged fixing means for the electrical cables, for example a disk 12 equipped with small metallic hooks which allow the winding and fixing in an ordered manner of the excess parts of the cables which connect the surveying means (A1-A5) of the meteorological data to the acquisition and memorisation means 11. The arms 8a and 8b carrying the meteorological surveying means A2 and A3 at their distal ends are preferably oriented in such a manner as to be arranged at approx 120° to one another and at approx. 60° from the legs 2 which instead hold the distal floating means 3b. The orientation of the arms 8a and 8b position the. meteorological surveying means A2 and A3 as far away as possible from such floating means 3b, allowing the carrying out of the measurement of the meteorological variables in canopy conditions as undisturbed as possible. However, such an orientation of the arms 8a and 8b also unbalances the structure of the weather station, making the shaft 4 flex in the direction of the bisector of the angle formed by the arms 8a and 8b, which support the meteorological surveying means A2 and A3. In order to solve this problem, an additional balancing arm 13 may be positioned on the shaft 4 at a pre-fixed height (for example of approx. 100-110 centimetres from the base) , arranged at approx. 120° with respect to arms 8a and 8b. The distal end of the arm 13 is equipped with counter-weighting means (not shown) . Preferably, stabilisation comes about through the connection through the tie-beam of the distal end of the arm 13 to the point of insertion of the supports into the inner floating means 3a.

Finally, one thermometric sensor A5 (not shown) may be positioned on the bottom of the water basin connected by a cable to the acquisition and memorisation means 11 of the meteorological data. Such thermometric sensor A5 will preferably be associated with anchorage means to the bottom of the basin, such as a weight .

The shaft 4, the supporting legs 2 for the floating means 3a and 3b, the arms 8a and 8b holding the meteorological surveying means A2 and A3 respectively, the arm 6 and the balancing arm 13 are preferably of a tubular structure, preferably consisting of tubes of aeronautical grade aluminium. The joining means and the structures connecting the legs 2 and the various arms 6, 8, 13 to the shaft 4 are made either from solid blocks of aeronautical grade aluminium or of plastic material or a combination thereof.

The meteorological _surveying means A2, A3 and A4, which are fixed, with appropriate fixing means, to the side arms 8a and 8b and to the top of the shaf 4 , respectively, preferably comprise, as mentioned above, thermometric sensors 28 and shielding means 9a, 9b, 9c. Said meteorological surveying means are represented diagrammatically, with particular example of the surveying means A2, in figures 4 and 5. These comprise a supporting structure preferably consisting of an upper disk 30 and a base ring 31 which are mutually connected by three rods 32, which in turn support a Pagoda-like structure formed by a series of conical bodies 33.^' To the three rods 32 which support the upper disk are also connected spacers onto which the aforementioned conical bodies 33 rest. Such shielding means 9a, 9b, 9c define an inner space inside which is found the thermometric sensor 28. The shielding means 9a, 9b, 9c have the function of protecting the thermometric sensor from solar radiation and from weathering agents, but at the same time allow ^' the passage of air and therefore the correct measurement of the temperature by the thermometric sensor 28.

According to one possible embodiment, the floating weather station 1 is additionally equipped with a water level measuring device, diagrammatically represented in figure 6. A level indicator is indicated overall with the numeral 15.

With reference to figure 6, the level indicator 15 comprises a cog-belt 16 equipped at one end with floating means 17 and at the opposite end with counter-weighting means 18. The floating means 17 are rested on the surface of the water and fluctuate vertically following the changes of the level of the surface of the water itself. The counter-weighting means 18 serve to maintain the cog-belt 16 under tension. The cog-belt 16 is moved along a three-pulley system 19a, 19b, 20. Particularly, such pulley system comprises two return pulleys 19a, 19b arranged in relation to each other with their axes lying in a horizontal plane and one cog-pulley 20 which is arranged between the two pulleys 19a, 19b, but in a lower position. The positions of the pulleys 19a, 19b, 20 are such as to form a wide supporting arch between the cog-belt 16 and the cog-pulley 20. This allows the attainment of maximum overlapping between the teeth of the cog-pulley 20 and the cog-belt 16, respectively, in such a manner as to obtain the distribution of the forces over several teeth, allowing a more accurate measure of the movement of the cog-belt 16. The cog-pulley 20, drawn by the cog-belt 16, is rotatingly integral with the handle of a potentiometer 21. The latter detects the relative movements of the cog-pulley 20 and the cog-belt 16 which are due to the changes in the level of the water surface. The potentiometer 21 is supplied by a battery 22. Between the battery 22 and the potentiometer 21 a circuit system 23 is inserted which is able to make the output voltage from the battery itself constant.

The potentiometer 21 is therefore able to detect with high precision the exact level of the surface of the water as the potential difference due also to the turns of the cog-pulley 20, drawn by the belt 16 and associated with the handle of the potentiometer 21. The changes in output potential from the potentiometer are recorded by the acquisition and memorisation means, i.e.' by a data recording device . Such acquisition and memorisation means of the water level data may be positioned on the level detecting device 15 itself or on the floating weather station 1. The water surface level measuring device 15, may be comprised within the floating weather station or be separate from it. In this latter sense, the water surface level detection device 15 represents an additional object of the present invention. From what has been described above, the advantages of the weather station according to the present invention are immediately apparent .

Indeed, the floating structure of the weather station and the arrangement at different heights of the surveying means of the meteorological data, allow for the conditions and the meteorological situation actually existing at the level of the canopy to be measured. In order to study the thermal profile in paddy fields, it is in fact necessary to measure the meteorological variables within the vegetation itself and at various distances from the water surface. Accordingly, in the particular embodiment of the above described weather station, the structure has meteorological data surveying means positioned at well established critical heights, that is on the bottom of the basin (the sensor associated with the means of meteorological surveying A5) , on the water surface (the sensor associated with the means of meteorological surveying Al) , inside the area of the vegetation covering the surface of the water (the sensor associated with the means of meteorological surveying A2) , at the edge of said area (the sensor associated with the meteorological surveying means A3) and above said area (the sensor associated with the meteorological surveying means A4) . This solution allows, besides monitoring the meteorological variations in the individual areas of the canopy, above all the surveying of the vertical temperature gradient above the water surface. An additional advantage of the particular embodiment of the weather station of the invention is the fact of it being very light. That allows the attainment of a maximum draft of approx. 4 cm below the water surface. This is very important considering water management within the paddy field and therefore the fact that the structure must be able to float even in only 5-6 cm of water. Furthermore, the lightness of the structure advantageously allows additional structural modifications to the particular embodiment of the above described weather station. Indeed , it is possible to install other means of meteorological data surveying without altering the floating characteristics of the weather station.

The possibility, according to the present invention, of providing the floating weather station with a water level detection device represents a third and fundamental advantage of the present structure. Indeed, it is thus possible to correlate the variations of the water level with the measurements of the meteorological variables, in such a manner, determining the temperature gradient within the canopy as a function of the water basin water level. This allows evaluating with precision, the true conditions present at the level of the' canopy and allows studying the effect "of the thermal draughts exerted by the water itself.

A final advantage of the floating weather station according to the present invention, is the achievement of a scarcely invasive structure, which therefore, thanks to the corresponding arrangements of the various arms to which the meteorological data surveying means are fixed, and the reduced dimensions of the floats, is placed amongst the vegetation without disturbing the latter. This allows for maintaining the environment within which the meteorological data must be collected, as undisturbed as possible.

It is evident that only one embodiment of the floating weather station forming the object of the present invention has been described, to which the expert in the art will be able to bring about all the modifications necessary for the adaptation thereof to any particular applications, without moreover departing from the scope of protection of the present invention.

For example, the number and type of the meteorological surveying means may vary according to requirements. Besides the thermometric sensors, radiometers, hygrometers, pluviometers and/or anemometers for example may therefore be installed onto the structure. In particular, two radiometers may be installed, one pointing upwards (radiation) and the second pointed downwards (albedo) . In the presence of one embodiment of the weather station according to the invention comprising various types of meteorological data surveying means, will be envisaged multi-input data acquisition and memorising means for the collection of information in connection with all the different meteorological variables (temperature, radiation, albedo, wind speed, water depth, etc.) always as a function of the distance from the water surf ce .

Furthermore, it is to be remarked on that the weather station according to the present invention may be also used in applications other than those described herein, i.e. in paddy fields, and more generally, could be used in all those cases wherein the determination of the meteorological variables in water basins is desired.

Claims

1. A floating weather station (1) for the measurement of meteorological variables in a water basin, able to float in only a few centimetres of water, comprising a supporting structure (100) , floating means (3a, 3b) and meteorological surveying means (A1-A5) connected to said supporting structure, characterised in that said supporting structure comprises a base constituted by at least three legs (2) arranged radially and symmetrically, and a shaft (4) extending upwards from the point of conjunction of the legs (2) .

2. The floating weather station according to claim 1, wherein said legs (2) and said shaft (4) are tubular structures.

3. The floating weather station according to claims 1 or 2, wherein said legs (2) and said shaft (4) are made from aeronautical grade aluminium.

4. The floating weather station according to any of the claims 1 to 4, wherein said legs (2) are three and are arranged radially at approx. 120° to one another.

5. The floating weather station according to any of the preceding claims wherein first floating means (3a) are arranged at the conjunction point of the legs (2) with the shaft (4) and second floating means (3b) are arranged in close proximity to the distal end of each leg (2) .

6. The floating weather station according to any of the claims 1 to 5, wherein said floating means

(3a, 3b) have a surface capable of reflecting radiation, preferably a white surface.

7. The floating weather station according to any of the claims 1 to 6, wherein said floating means (3a, 3b) consist of polyeurethane sheets.

8. The floating weather station according to any of the preceding claims, further comprising anchorage means (2a) of the floating weather station (1) to the bottom of the basin.

9. The floating weather station according to claim 8, wherein said anchorage means (2a) are arranged on at least one leg (2) .

10. The floating weather station according to claims 8 or 9, wherein said anchorage means (2a) comprise fixing members (24) to the leg (2) , said fixing members (24) being preferably a bored body, in the throughole of which said leg (2) is slidingly housed, and anchorage members (25) , said anchorage members (25) being preferably formed by a slotted member (26) into which a peg (27) is inserted.

11. The floating weather station according to any of the preceding claims, wherein said means of meteorological surveying (A1-A5) are selected from thermometric sensors, radiometers, hygrometers, pluviometers and/or anemometers.

12. The floating weather station according to any of the. preceding claims, wherein said means of meteorological surveying (A1-A5) comprise a plurality of thermometric sensors arranged at heights above the water surface of the water basin such as to allow the measurement of a gradient as a function of the distance from the water surface.

13. The floating weather station according to claim 12, wherein first meteorological surveying means (Al) comprise a thermometric sensor (28) and floating shielding means (7) .

14. The floating weather station according to claim 13, wherein said floating shielding means (7) have a disk-like shape comprising a semi-cylindrical arched central part (7a) , developing along the diameter of said disk and two half-moon shaped flat outer parts, comprising floating means.

15. The floating weather station according to claim 14, Wherein said thermometric sensor (28) is hanged below said arched central part (7a) of said floating shielding means (7) .

16. The floating weather station according to any of the claims 13 to 15, wherein said thermometric sensor (28) is positioned submerged under the water surface .

17. The floating weather station according to claim 16, wherein said thermometric sensor (28) is positioned at a depth of approx. 1 cm below the water surface .

18. The floating weather station according to any of the claims 14 to 17, wherein said first means of meteorological detection (Al) are arranged at the distal end of one arm (6) connected through vertical joining means (5, 6b) to the shaft (4) .

19. The floating weather station according to any of the preceding claims, wherein second meteorological surveying means (A2) are positioned at a height .comprised of between 30 to 40 centimetres from the attachment point of the shaft (4) to the conjunction point of the legs (2) , and are connected to said shaft (4) through an arm (8a) .

20. The floating weather station according to any of the preceding claims, wherein third meteorological surveying means (A3) are positioned at a height comprised of between 60 to 70 centimetres from the attachment point of the shaft (4) to the conjunction point of the legs (2) , and are connected to said shaft (4) through an arm (8b) .

21. The floating weather station according to any of the claims 19 or 20, wherein said arms (8a, 8b) form an angle of approx. 120° between one another and of approx. 60° with said legs (2) .

22. The floating weather station according to any. of the preceding claims, wherein fourth meteorological surveying means (A4) are positioned at a height comprised of between 140 to 200 centimetres from the attachment point of the shaft (4) to the conjunction point of the legs (2) .

23. The floating weather station according to any of the. claims 19 to 22, wherein said meteorological surveying means (A2, A3, A4) comprise a thermometric sensor (28) and shielding means (9a, 9b, 9c) .

24. The floating weather station according to claim 23, wherein said shielding means (9a, 9b, 9c) comprise a. supporting structure consisting of an upper disk (30) , a base ring (31) , connected together by rods (32) , and a Pagoda-like structure formed by a stack of spaced out conical bodies (33) , characterised in that it defines an inner space inside which said thermometric sensor (28) is positioned.

25. The floating weather station according to any of the preceding claims, wherein fifth meteorological surveying means (A5) are placed on the bottom of the water basin.

26. The floating weather station according to any of the -preceding claims, additionally comprising acquisition and memorisation means (11) of meteorological data.

27. The floating weather station according to any of the preceding claims, further comprising a balancing arm (13) , equipped with means of counter weighting at distal end thereof.

28. The floating weather station according to claim 27, wherein said balancing arm (13) forms an angle of approx. 120° with said arms (8a, 8b) .

29. The floating weather station according to any of the preceding claims, further comprising a water level detection device (15) .

30. The floating weather station according to claim 29, wherein said water ^' level detection device (15) comprises a cog-belt (16) , equipped at one end with floating means (17) and at the other end with counter weighting means (18) , a return pulley (19a, 19b) and cog-pulley (20) system, around which said cog-belt (16) is wound, a potentiometer (21) , the handle of which is rotatingly integral with the cog- pulley (20) , said potentiometer (21) being supplied by a battery (22) , a .circuit (23) inserted between said potentiometer (21) and said battery (22) , in order to make the output voltage from said battery constant, and acquisition and memorisation means of the water level data as a function of the changes in potential.

31. The floating weather station according to claim 30, wherein said of acquisition and memorisation means of the water level data are either positioned on said detection device (15) or on the floating weather station itself.

32. A detection device (15) for the level of the water as described in claim 30.

33. A floating weather station (1) for the measurement of meteorological variables in a water basin, able .to float in a few centimetres of water, comprising a supporting structure (100) , floating means (3a, 3b) and meteorological surveying means

(A1-A5) connected to said supporting structure, characterised in that said meteorological surveying means (A1-A5) comprise a plurality of thermometric sensors arranged at heights from the water basin water surface such as to allow the measurement of a gradient as a function of the distance from the water surface.

34. The floating weather station according to claim 33, wherein at least one of said thermometric sensors is arranged under the surface of the water and is screened from solar radiation by floating, aerated screening means (7) .

35. The floating weather station according to claim 34, wherein said thermometric sensor is fixed to said floating screening means (7) in such a manner as to maintain a constantly submerged condition, preferably of around a depth of 1 cm.