SEEDING AND VERIFICATION METHOD FOR TARGETTED

CLOUD SEEDING

Technical Field

[1] The present invention relates to a seeding and verification method for targeted cloud seeding, and more particularly, to a seeding and verification method for targeted cloud seeding which can precipitate snow or rain in a local area. Background Art

[2] Considering that available water resources are limited whereas growing population and economic development increase demand for water resources, all areas will face water shortages in the future. According to Population Action International (PAI) under the United Nations (UN), Koreans consume 1520 tons of water per capita per year. Thus, Korea is classified as a water shortage country like Libya, Morocco, Egypt, Oman, etc.

[3] The average annual rainfall in Korea is 1,310mm, which is higher than the global average. However, the annual rainfall per capita is only 12.5% of the world average. Further, Korea gets most of the average annual rainfall in the summer season, and the rainfall is significantly varied depending on locations and seasons. Furthermore, river basins have steep slopes, thereby making it difficult to efficiently acquire water resources.

[4] In particular, Gangwon province has an average annual rainfall of 1,400 ~ 1,800mm and is classified as a humid zone. However, the annual rainfall is concentrated in the summer season, winter rainfall is very low, and spring rainfall is merely 15% of the annual rainfall. According to climatology, drought occurs when the annual rainfall is equal to or less than 75% of a normal value, and severe drought occurs when the annual rainfall is equal to or less than 50%. Thus, Gangwon province is classified as a drought zone in the winter and spring seasons.

[5] As a method of developing auxiliary water resources under conditions that water resources from nature are restricted, cloud seeding may be an alternative proposal for increasing the water resources supplied from nature.

[6] Herein, cloud seeding refers to a technology that makes rain in a certain area by artificially dispersing "cloud seeds" in air when cloud droplets do not grow into precipitation due to lack of ice nuclei or cloud condensation nuclei in air despite the presence of a cloud layer. This technique has been studied since the 1946 and has already been put to practical use in the United States, Russia, and the like. Further, technical development of cloud seeding has proceeded in 40 countries. [7] Until recently, the cloud seeding experimentation has utilized an airplane to precipitate rain over a broad area, but a seeding and verification method for targeted cloud seeding have not yet been developed. Thus, there is a need to develop a seeding and verification method for targeted cloud seeding. Disclosure of Invention Technical Problem

[8] The present invention is conceived to solve the foregoing problems, and an aspect of the invention is to provide a seeding and verification method for targeted cloud seeding which can restrictively precipitate rain or snow in a target area on the basis of topographical features of a certain region, for example the Taebaek Mountains or the like, and the direction and speed of wind in the certain region, to thereby acquire water resources, alleviate and prevent weather disasters, provide a leisure environment, permit power production using the water resources, and facilitate research into cloud physics. Technical Solution

[9] In accordance with an aspect, a seeding and verification method for targeted cloud seeding includes: moving to a windward side of a target area for cloud seeding; previously dispersing cloud seeds towards a location at the windward side of a target area such that the cloud seeds arrive after a lapse of a set time if the target area satisfies given weather conditions; and verifying a cloud seeding effect using an instrument for measuring a drop size distribution and an aviation radar from a seeding area to a target area.

[10] The previously dispersing cloud seeds may include dispersing the cloud seeds towards a cloud top or into a cloud so as to cross a direction of wind blowing from the targeted windward side.

[11] The previously dispersing cloud seeds may include dispersing the cloud seeds if a temperature of the seeding area is not less than -4O ⁰ C and not more than -5 ⁰ C.

[12] The previously dispersing cloud seeds may include dispersing the cloud seeds 5 km from the target area if the wind has a speed less than 3m/s.

[13] The previously dispersing cloud seeds may include dispersing the cloud seeds 10 km from the target area if the wind has a speed of 3 to 6 m/s.

[14] The previously dispersing cloud seeds may include dispersing the cloud seeds throughout an area of 100 km2.

Advantageous Effects

[15] According to embodiments of the invention, the seeding and verification method for targeted cloud seeding can restrictively precipitate rain or snow in a target area on the basis of topographical features of a certain region, for example, the Taebaek Mountains, and the direction and speed of the wind in the certain region, to thereby acquire water resources, alleviate and prevent weather disasters, provide a leisure environment, permit power production using the water resources, and facilitate research into cloud physics. Brief Description of Drawings

[16] Fig. 1 is a flowchart of a seeding and verification method for targeted cloud seeding in accordance with an embodiment of the present invention; and

[17] Figs. 2 and 3 are conceptual views of the seeding and verification method for targeted cloud seeding. Best Mode for Carrying out the Invention

[18] Embodiments of the invention will now be described with reference to the accompanying drawings.

[19] Referring to Figs. 1 to 3, a seeding and verification method for target cloud seeding according to one embodiment of the invention includes cloud seeding preparation (SlO), movement to a windward side of a target area (S20), clod seed dispersion (S30), and cloud seeding effect verification (S40) using an instrument for measuring a drop size distribution and an aviation radar from a seeding area to the target area.

[20] In the cloud seeding preparation (SlO), advance preparations and inspection are made for an airplane for the cloud seeding, a cloud seed sprayer installed in the airplane, silver iodide, liquid nitrogen gas, a disdrometer, a radar, an aeronautic global positioning system (GPS), an oil pressure gage, an aeronautic transceiver, etc.

[21] In the movement to the windward side of the target are (S20), the airplane with the cloud seed sprayer or the like moves to a cloud seeding area to perform the cloud seeding in a predetermined target area (a ski resort or the like) in in-land areas, for example, Yeongseo area of Gangwon province in South Korea. The cloud seeding area is checked through the aeronautic GPS, and the airplane moves to the cloud seeding area and receives notification of wind speed at an altitude for the cloud seeding from a ground supervisor through the aeronautic transceiver. Here, the altitude for the cloud seeding is varied depending on the cloud top.

[22] In the clod seed dispersion (S30), if the cloud seeding area satisfies certain weather conditions, seeding substances are artificially dispersed as the cloud seeds from the cloud seeding sprayer at the targeted windward side, i.e., various particles acting as the ice nuclei or the cloud condensation nuclei are artificially dispersed to cause the rainfall. For example, in South Korea, the cloud seeds may be dispersed under the typical weather conditions of South Korea wherein high atmospheric pressure dominates at the north and low atmospheric pressure dominates at the south the (i.e., north-high and south-low patterns), and when clouds over the East Sea are introduced into the Taebaek Mountains by easterly winds in the state that the cloud seeding area is at a temperature of -4O ⁰ C and not more than -5 ⁰ C.

[23] That is, in the cloud seed dispersion (S30), when the clouds introduced from the East

Sea by the easterly wind are advected and anabatically carried along the Taebaek Mountains to be supersaturated, these clouds are artificially seeded to precipitate snow or rain in the target area. The clouds that ride on northeasterly wind and pass over the Taebaek Mountains have the best conditions to precipitate snow or rain when seeded because they are lacking in cloud seeds even though humidity in the clouds increases as atmosphere undergoes adiabatic expansion at high altitudes. Accordingly, the cloud seeding is performed under the condition that the cloud seeding area has a temperature of -4O ⁰ C and not more than -5 ⁰ C, thereby causing snow or rain.

[24] As a result, when the clouds introduced from sea in winter and supersaturated while passing over the Taebaek Mountains have an insufficient amount of ice nuclei or cloud condensation nuclei to grow into snow or rain, the airplane artificially disperses the cloud seeds such as silver iodide (AgI) , liquid nitrogen gas (LN2) or dry ice to the cloud top or the cloud penetrations, so that precipitation can restrictively fall in a target area on the basis of the topographical features of the Taebaek Mountains and the direction and speed of the wind.

[25] In this embodiment, an experiment flight area for the cloud seeding of the target area was the Yeongseo area of Gangwon province. There is an ample hope for success in the experiment for the cloud seeding if the clouds are seeded when the easterly wind of Gangwon province is introduced due to the north-high and south-low patterns under the weather conditions of the Korean Peninsula and when the clouds are advected and anabatically carried along the Taebaek Mountains to be supersaturated. Particularly, Gangwon province is a representative mountainous region of South Korea, in which the Taebaek Mountains lead from the south to the north with the sea across the inland, and sub-zero temperatures continue from November to March, so that it is proper for the cloud seeding experiment. Further, the method of dispersing the ice nuclei or the cloud condensation nuclei using the anabatic wind at the windward side of the mountain area is the most likely to succeed among the methods hitherto known for cloud seeding.

[26] In the cloud seed dispersion (S30), the cloud seeds are dispersed towards the cloud top or into the cloud to cross the direction of the wind blowing from the windward side of the target area. If the wind speed is less than 3m/s, the cloud seeds are dispersed at a windward side area distant from a target area by 5km. If the wind speed is not less than 3m/s and not more than 6m/s, the cloud seeds are dispersed at a windward side area distant from a target area by 10km.

[27] That is, when the clouds introduced by the easterly wind are advected and an- abatically carried along the Taebaek mountains and become supersaturated, a seeding position is expected determined on the basis of the direction and speed of the wind, so that the cloud seeds can be dispersed previously.

[28] For example, silver iodide (AgI) is dispersed once per 10km of a seeding path, so that the area for the cloud seeding can be 100km2 from multiplication of length by width, but not limited thereto. Alternatively, the area for the cloud seeding may be increased or decreased.

[29] In the verification (S40) of the cloud seeding effect using an instrument for measuring a drop size distribution and an aviation radar from the seeding area to the target area, the radar (not shown) and the disdrometer (not shown) are used to measure and verify change in the precipitation of the target area, especially, before and after the experiment. Here, the change in radar reflectivity before and after the experiment for measuring the precipitation and the drop size distribution of the precipitation measured by the disdrometers in the seeding area and the target area at the same time are compared and analyzed. When comparing the change in the radar reflectivity and the drop size distribution from the seeding area to the target area before and after the experiment, it can be seen that the drop size distribution of the precipitation is increased during the experiment.

[30] Accordingly, the seeding and verification method for the cloud seeding according to an exemplary embodiment of the present invention first maintains and prepares various devices in the state that the devices for dispersing the cloud seeds are mounted to the airplane.

[31] Next, the airplane moves to the windward side of the target area for the cloud seeding, and artificially disperses the cloud seeds towards the cloud top or into the cloud so as to cross the direction of the wind blowing from the windward side of the target area.

[32] At this time, the seeding position is determined on the basis of the direction and speed of the wind when the clouds introduced by the easterly wind are advected and anabatically carried along the Taebaek mountains and become supersaturated in the state that the weather conditions have the north-high and south-low patterns and the cloud seeding area has a temperature of -4O ⁰ C and not more than -5 ⁰ C, so that the cloud seeds can be dispersed previously.

[33] Then, the radar (not shown) and the disdrometer (not shown) for measuring the drop size distribution are used to measure and verify the change in the precipitation of the seeding area and the target area, especially, before and after the experiment.

[34] Consequently, according to the embodiment, the seeding and verification method for targeted cloud seeding can restrictively precipitate rain or snow in a target area on the basis of topographical features of a certain area, for example, the Taebaek Mountains, and the direction and speed of the wind in the certain region, so that floods and artificial weather disasters due to rainfall in an unspecified area can be prevented. Further, advantages of the cloud seeding such as water-resource acquisition, drought resolution and the like can be ensured by limiting the cloud seeding to the target area, and the cloud seeding can be artificially performed and verified in the target area without depending on the direction of wind with large uncertainty even when the wind is easterly. [35] Although the invention has been described with reference to the embodiments, the invention is not limited to these embodiments. It will be apparent to those skilled in the art that various modifications, additions and substitutions can be made without departing from the scope and spirit of the invention as limited only by the accompanying claims and equivalents thereof.