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CN-121995547-A - Method for discriminating freezing rain and snowfall in winter

CN121995547ACN 121995547 ACN121995547 ACN 121995547ACN-121995547-A

Abstract

The invention discloses a method for distinguishing freezing rain and snowfall in winter, and relates to the technical field of weather. According to the invention, by acquiring research samples of ground automatic weather station, sounding and wind profile radar observation data in winter, preprocessing the ground automatic weather station, sounding and wind profile radar observation data, extracting physical quantity parameters, statistically analyzing the characteristics of vertical speed, horizontal wind speed and horizontal wind direction at 5 heights of ground 2 meters of air temperature, 700 hundred pascals of air temperature, 500 hundred pascals of air temperature, potential thickness between 500 hundred pascals and 700 hundred pascals, 0 degree layer height, cloud top temperature, (150 meters, 390 meters, 750 meters, 1350 meters and 2430 meters), combining specific layer temperature with precipitation particle vertical speed, establishing optimal freezing rain and snowfall discrimination indexes, and improving the discrimination capability of freezing rain and snowfall.

Inventors

  • LI CUICUI
  • SHI YUANZHE
  • REN HENGYI
  • WANG XIAOLAN
  • YANG ZHE

Assignees

  • 贵州省气象数据中心

Dates

Publication Date
20260508
Application Date
20260209

Claims (8)

  1. 1. The method for distinguishing the freezing rain and the snowfall in winter is characterized by comprising the following steps of: S1, acquiring ground automatic weather station observation data, sounding observation data and profile radar observation data of a target area in winter to form a research sample set; S2, preprocessing various observation data in the research sample set, and extracting physical quantity parameters for discrimination from the preprocessed observation data; S3, based on the extracted physical quantity parameters, respectively carrying out statistical analysis on the distribution characteristics of the physical quantity parameters under the freezing rain event and the snowfall event; S4, establishing a distinguishing index of freezing rain and snowfall according to the distribution characteristics and by combining with the geographical and climatic characteristics of the target region; S5, acquiring corresponding real-time observation data according to weather process to be discriminated, extracting physical quantity parameters according to the discrimination indexes, and outputting discrimination results of freezing rain or snowfall according to the discrimination indexes.
  2. 2. The method according to claim 1, wherein the physical quantity parameters extracted from the ground automatic weather station observation data in the step S2 are ground 2m air temperature, the physical quantity parameters extracted from the sounding observation data include 700 and 500 hundred pascal specific layer temperature, 700 and 500 hundred pascal potential height, 0 degree layer height and cloud top temperature, and the physical quantity parameters extracted from the wind profile radar observation data include at least 5 vertical speed, horizontal wind speed and horizontal wind direction parameters at different heights.
  3. 3. The method according to claim 2, wherein the 0 degree layer height is a difference between a potential height of a lowest 0 degree layer on the sounding height and the altitude.
  4. 4. The method for distinguishing freeze rain and snowfall in winter according to claim 3, wherein the cloud top temperature is calculated by extracting the temperature and the dew point temperature from a exploratory research sample, and taking the temperature of which the difference is less than 3 ℃ as the cloud top temperature.
  5. 5. A method for discriminating winter freezing rain and snowfall according to claim 4 wherein said distribution characteristics statistically analyzed in step S3 include a distribution characteristic of 2 meters air temperature of freezing rain and snowfall ground, a distribution characteristic of potential thickness between 500 and 700 hundred Pa of freezing rain and snowfall, a distribution characteristic of 0 degree layer height of freezing rain and snowfall, a distribution characteristic of freezing rain and snowfall cloud top temperature, and a vertical velocity, horizontal wind velocity and horizontal wind direction distribution characteristic of freezing rain and snowfall at least 5 different heights.
  6. 6. The method according to claim 5, wherein the heights of the physical quantity parameters and the distribution characteristics are set to 5, and are set to 150 meters, 390 meters, 750 meters, 1350 meters, 2430 meters, respectively.
  7. 7. The method for determining whether the target area is full-scale in the winter according to claim 6, wherein in the step S4, the freezing rain and snowfall determining indexes are: When the temperature of 2 meters on the ground is less than or equal to 0 ℃, the temperature of the cloud top is more than or equal to-9 ℃ and the vertical speed of 1350 meters is less than or equal to 0.6m/s, judging that the water-cooled solar energy water heater is freezing rain; and when the temperature of 2 meters on the ground is less than 1 ℃, the temperature of the cloud top is less than or equal to-12 ℃, and the vertical speed of 1350 meters is greater than 0.6m/s, determining that the snow is reduced.
  8. 8. The method for determining whether the target area is a middle area of Guizhou, according to claim 6, wherein in the step S4, the determining indexes of the freezing rain and the snowfall are as follows: And judging that the freezing rain is generated when the ground temperature is less than or equal to 0 ℃, the temperature is more than-3 ℃ and the potential thickness between 500 and 700 hundred pascals is more than or equal to 263 dagpm.

Description

Method for discriminating freezing rain and snowfall in winter Technical Field The invention relates to the technical field of weather, in particular to a method for distinguishing freezing rain and snowfall in winter. Background In the winter, the mixed precipitation is also a difficult point for weather forecast in the Guizhou, such as precipitation, freezing rain, snow and the like, and the mixed precipitation of freezing rain and snow is easy to form freezing weather, so that the mixed precipitation has great influence on transportation, agricultural production, communication facilities, power transmission, energy supply and life of people. A plurality of students utilize ground, exploration, re-analysis and other data to research rainfall phases such as rainfall, freezing rain, snow and the like, and mainly research rainfall phase or rainfall-rain-snow-snowfall multiphase rainfall identification indexes. If Jing Hao and the like are used for researching the winter precipitation phase states in Beijing and surrounding areas, the cloud top temperature and the layer height of 0 ℃ are used as key elements for judging the phase states, and the result shows that the cloud top temperature is less than or equal to-14 ℃ which is an important threshold for judging ice-phase particles with enough snowflakes in the cloud, is a necessary condition for snowfall, and is more easy to cause rain and snow inclusion or rainfall when the cloud top temperature is between-14 ℃ and-4 ℃. The wind profile radar can detect and obtain the falling end speed of precipitation particles and the vertical speed of air flow, kong Zhaolin and the like define the falling end speeds of rainfall and snowfall particles by utilizing the wind profile radar, and the falling end speeds are not reflected in the winter precipitation multiphase state discrimination indexes. Wu Guhui and the like are used for analyzing low-temperature rain and snow weather in Guizhou in 2011 to obtain close relation between cloud top temperature and precipitation phase, the cloud top temperature is required to be low when snowfall occurs, and corresponding indexes of the cloud top temperature in Guizhou freezing rain and snowfall are not clear. However, because the vertical distribution of the temperature and the humidity in the atmosphere is very complex, different precipitation phases are also influenced by the underlying surfaces such as topography and the like, and the problem of low accuracy in distinguishing freezing rain and snowfall still exists in the prior art. Therefore, the invention provides a method for distinguishing freezing rain and snowfall in winter, which improves the accuracy of distinguishing the freezing rain and the snowfall in Guizhou. Disclosure of Invention (One) solving the technical problems Aiming at the defects of the prior art, the invention prepares the research samples of the ground automatic weather station, the sounding and the wind profile radar observation data in winter, preprocesses the ground automatic weather station, the sounding and the wind profile radar observation data, extracts physical quantity parameters, statistically analyzes the vertical speed, the horizontal wind speed and the horizontal wind direction distribution characteristics at 5 heights of ground 2 meters air temperature, 700 hundred pascal air temperature, 500 hundred pascal air temperature, potential thickness between 500 hundred pascal and 700 hundred pascal, 0 degree layer height, cloud top temperature, (150 meters, 390 meters, 750 meters, 1350 meters and 2430 meters), combines the specific layer temperature with the vertical speed of precipitation particles, establishes optimal freezing rain and snowfall discrimination indexes, and can improve the discrimination capability of freezing rain and snowfall. (II) technical scheme In order to achieve the purpose, the invention provides the following technical scheme that the method for distinguishing the freezing rain and the snowfall in winter comprises the following steps: S1, acquiring ground automatic weather station observation data, sounding observation data and profile radar observation data of a target area in winter to form a research sample set; S2, preprocessing various observation data in the research sample set, and extracting physical quantity parameters for discrimination from the preprocessed observation data; S3, based on the extracted physical quantity parameters, respectively carrying out statistical analysis on the distribution characteristics of the physical quantity parameters under the freezing rain event and the snowfall event; S4, establishing a distinguishing index of freezing rain and snowfall according to the distribution characteristics and by combining with the geographical and climatic characteristics of the target region; S5, acquiring corresponding real-time observation data according to weather process to be discriminated, extracting physical quantity parameters according