What does the Meteorological Observatory mean when it says 100 rainfall?

100% means that the probability is very high, and there is a sense of certainty, so 100% rain means that it will definitely rain.

It is called a heavy rainstorm. The depth of the water layer in any part of the rainfall area without evaporation or infiltration is 100 mm.

Light rain, moderate rain, heavy rain, heavy rain, etc., are generally measured in daily rainfall. Among them, light rain refers to daily rainfall of less than 10 mm; Moderate rainfall of 10 mm on a day; Heavy rainfall of 25 mm; Heavy rainfall of 50 mm; Heavy rainfall of 100 250 mm; Heavy rainfall of more than 250 mm.

Measurement of rainfall.

Meteorology and hydrology are mainly used to measure rainfall, and the main tools are tipping bucket rainfall sensors. This kind of measuring device flows the received rainfall into a small bucket, and when it reaches a certain amount, it is automatically discarded, and at the same time forms a corresponding rainfall record. Meteorology uses millimetre tipping bucket rain sensors, while hydrology uses millimetres.

Tipping bucket rain sensors are more advanced measuring instruments that automatically generate rainfall records, as they previously used rain gauges and measuring cups.

The rain gauge is generally 20 cm in diameter and contains a funnel and a bottle. The measuring cup has a diameter of 4 cm, and it is used with a rain gauge. When measuring, pour the rainwater from the rain scale into the measuring cup, and the amount of rainfall in the corresponding period can be known according to the scale on the cup.

100 mm of rainfall is considered heavy rainfall. Rainfall refers to the depth of the water layer that has accumulated on the water surface without evaporation, infiltration, and loss of rainfall from the sky to the ground, generally in millimeters, which can intuitively indicate the amount of rainfall. Rainfall is an important basis for calculating regional water resources, so it is necessary to find an accurate and easy way to increase rainfall.

Rainfall measurementsRainfall is generally measured with a rain measuring cylinder, so precipitation may contain small amounts of dew, frost, and pine. In meteorology, there are often yearly, monthly, daily, 12-hour, 6-hour or even 1-hour precipitation, and the rain and snow that falls in 6 hours all melt into water, which is called 6-hour precipitation; All the rain and snow that falls in 24 hours melt into water, which is called 24-hour precipitation.

All the rain and snow that falls in a decade melt into water, which is called the ...... precipitationOver the course of a year, all the rain and snow that falls melt into water, which is called "annual precipitation". The amount of liquid precipitation is called rainfall, and sometimes the two are also used as synonyms. The amount of precipitation per unit of time is called precipitation intensity, which is usually measured in mm h or mm min.

The amount of rainfall per unit of time is called rain intensity.

Rainfall (precipitated, as it should be called), refers to the depth at which liquid or solid (melted) water falls from the sky to the ground, without evaporation, infiltration, or loss, and accumulates on a horizontal plane.

A rainfall of 100 mm means that the rain that falls over a period of time (which can be 1 hour or a period of time such as 24 hours) accumulates at a depth of 100 mm, or 10 centimeters, or meters, on the water level.

With 100 mm of rainfall, if it is reached within 1 hour, it reaches the level of a heavy rainstorm.

The amount of rainfall mentioned here means that the rainfall reaches 100 mm according to this hour, that is, the rainfall is very large.

That is, the depth of precipitation, which can reach 10 centimeters, that is, 1 decimeter.

Discharge cooling is another type of convection cooling. Unlike regenerative cooling, the coolant used for exhaust cooling absorbs heat to the thrust chamber and is discharged out of the combustion chamber instead of entering the combustion chamber to participate in combustion. Direct drain coolant reduces the thrust chamber specific impulse, so the coolant flow for drain cooling needs to be minimized while only using drain cooling at the outlet section of the nozzle that is relatively less heated.

There is also radiative cooling, in which the heat flow is transferred from the combustion products to the thrust chamber, and then the heat is radiated by the thrust chamber wall to the surrounding space. Radiative cooling is characterized by simplicity and small structural mass. It is mainly used in the extension section of large nozzles and the thrust chamber of small thrust engines using high-temperature resistant materials.

When cooling in the thrust chamber of the tissue, a relatively low temperature liquid or gas protective layer is established on the surface of the thrust chamber wall to reduce the heat flow to the thrust chamber wall, reduce the wall temperature, and achieve cooling. Internal cooling is mainly divided into three methods: internal cooling (shield cooling), membrane cooling and diaphoretic cooling of head tissues. After the internal cooling measures are adopted in the thrust chamber, the mixing ratio near the wall of the combustion chamber is different from the optimal mixing ratio in the central area (in most cases, the near-wall layer rich in fuel is used) due to the need to reduce the temperature of the protective layer, resulting in the uneven distribution of the mixing ratio along the cross-section of the combustion chamber, so that the combustion efficiency is reduced to a certain extent.

Membrane cooling is similar to shield cooling in that it cools the thrust chamber wall by establishing a uniform and stable coolant film or air film protective layer near the inner wall surface, except that the coolant used to establish the protective layer is not injected by the injector, but is supplied through a special cooling belt. The cooling band is generally arranged in a cross-section of the combustion chamber or the convergence section of the nozzle. There can be several cooling bands along the length of the combustion chamber.

In order to improve the stability of the membrane, the coolant often flows through the gaps or small holes in the cooling belts, and when sweating is used, the thrust chamber wall or part of the inner wall is made of porous material with a pore diameter of tens of microns. Porous materials are usually sintered with metal powders or pressed with metal mesh. In this case, the number of pores per unit area is increased by making the micropores in the material as evenly distributed as possible.

The liquid coolant penetrates into the inner wall, creating a protective film that reduces the density of the heat transferred to the wall. When the flow rate of liquid coolant used for sweat cooling is above a certain threshold, a liquid film is formed near the wall of the thrust chamber. When the coolant flow rate is below the critical flow, the inner wall temperature will be higher than the coolant boiling point at the current pressure, and some or all of the coolant will evaporate, forming an air film.

In addition to the above thermal protection, there are other thermal protection methods such as: ablation cooling, thermal insulation cooling, hot melt cooling and composite protection of chamber walls. 3. Thermal protection scheme of high enthalpy gas generator Based on the above methods and the actual situation, the thermal protection method of high enthalpy gas generator is obtained.

The combustion chamber of a high-enthalpy gas generator differs from that of a liquid rocket engine, eliminating the front thrust chamber part, making its structure simpler and more effective. Then, the thermal protection involved is the thermal protection part of the combustion chamber wall. As the fuel enters the combustion chamber, it quickly decomposes and releases large quantities.

100 millimeters of precipitation is equal to 100 liters of square meters of precipitation. If converted to the average depth of precipitation, 100 mm of precipitation is equal to 1 square meter of precipitation with an average depth of 1 meter.

1 millimeter of precipitation, if calculated according to the area of one acre of land, is equivalent to pouring cubic meters of water into one acre of land, that is, 667 kilograms of water.

From the point of view of precipitation distribution and annual precipitation, this unit mm is the most suitable, the general annual precipitation is more than 1,000 millimeters, generally hundreds or less, with mm this order of magnitude unit is just right, with other units is not easy to express, at the same time mm this unit has been accepted by most countries in the world, has become a unified unit, belongs to the default value.

Rainfall measurementsRainfall is generally measured with a rain measuring cylinder, so precipitation may contain small amounts of dew, frost, and pine. In meteorology, there are often yearly, monthly, daily, 12-hour, 6-hour or even 1-hour precipitation, and the rain and snow that falls in 6 hours all melt into water, which is called 6-hour precipitation; All the rain and snow that falls in 24 hours melt into water, which is called 24-hour precipitation.

All the rain and snow that falls in a decade melt into water, which is called the ...... precipitationOver the course of a year, all the rain and snow that falls melt into water, which is called "annual precipitation". The amount of liquid precipitation is called rainfall, and sometimes the two are also used as synonyms. The amount of precipitation per unit of time is called precipitation intensity, which is usually measured in mm h or mm min.

The amount of rainfall per unit of time is called rain intensity.

The depth of the water layer accumulated without evaporation, infiltration, or loss at any one point in the rainfall area is 100 mm.

You can understand that you can take a cylindrical cylinder to remove the water, and you can receive rainwater up to a depth of 100 mm anywhere in the rainfall area.

The depth of the water layer that rains from the sky to the ground, and the water layer that accumulates on the surface of the water without evaporation, infiltration, or loss, is called rainfall. 100 mm is the volume of rain that falls in a particular area at a specific time divided by the area of that land, which is the height.

The volume of water falling in the entire area is divided by the area to get a height, which is the amount of rainfall.

In layman's terms, it refers to the estimated height of rainwater stored on the ground, which is used to indicate how much rainfall is received.

That is, the rain from the sky is measured by area, and the average depth of water per square meter is 100 mm.

Use a cylindrical container to put it horizontally and measure the depth of the water after the rain.

The amount of rainfall per year divided by the area of the place is 100 mm!

The percentage of rain in the weather forecast refers to the likelihood of rain in a certain period of time. It is a probability value derived from meteorological data and models** that indicates how likely it is to experience rain in a given time frame. Generally speaking, the weather forecast will give a value of 100% to 70%, etc., which indicates the probability of rain during the corresponding time period.

A higher percentage of this percentage indicates a greater likelihood of rainfall, while a lower percentage indicates a lower likelihood of rainfall. It is important to note that the percentage of rain only indicates the likelihood of rainfall, not the exact amount or duration of rainfall. Therefore, even if the forecast shows a low percentage of rain, there is still a possibility of rainfall, while a higher percentage of rain indicates that there is a greater likelihood of rain.

If you're concerned about the percentage of rain in the weather forecast, you can use it to make arrangements accordingly, such as bringing rain gear, adjusting your outdoor activity plans, or paying attention to road safety.