- 行业: Weather
- Number of terms: 60695
- Number of blossaries: 0
- Company Profile:
The American Meteorological Society promotes the development and dissemination of information and education on the atmospheric and related oceanic and hydrologic sciences and the advancement of their professional applications. Founded in 1919, AMS has a membership of more than 14,000 professionals, ...
An analyzed chart of surface weather observations. Essentially, a surface chart shows the distribution of sea level pressure, including the positions of highs, lows, ridges, and troughs and the location and character of fronts and various boundaries such as drylines, outflow boundaries, sea-breeze fronts, and convergence lines. Often added to this are symbols of occurring weather phenomena, analysis of pressure tendency (isallobars), indications of the movement of pressure systems and fronts, and perhaps others, depending upon the intended use of the chart. Although the pressure is referred to mean sea level, all other elements on this chart are presented as they occur at the surface point of observation. A chart in this general form is the one commonly referred to as the weather map. When the surface chart is used in conjunction with constant-pressure charts of the upper atmosphere (e.g., in differential analysis), sea level pressure is usually converted to the height of the 1000-mb surface. The chart is then usually called the 1000-mb chart.
Industry:Weather
A significance test applicable to a sample mean of a sample estimate of a regression coefficient or a correlation coefficient (the latter only when the hypothetical value is zero). It is used to test an assumed value of the corresponding parameter. It is also applicable to the comparison of two (but not more than two) sample means or two regression coefficients, but not of two correlation coefficients. The ''t'' test has different formulas for different uses.
Industry:Weather
The portion of storm rainfall that is intercepted, stored in depressions, or otherwise sufficiently delayed that it fails to reach the basin outlet within the time interval of the storm hydrograph.
Industry:Weather
The portion of storm rainfall that is intercepted, stored in depressions, or otherwise sufficiently delayed that it fails to reach the basin outlet within the time interval of the storm hydrograph.
Industry:Weather
In clear-sky optics, the vertical plane defined by sun, zenith, and observer. The clear daytime sky's radiance, polarization, and chromaticity patterns are largely symmetric about the principal plane.
Industry:Weather
The net radiative flux density across a given point on the earth's surface, averaged over a specified time interval. Major components of the surface radiation budget are downward shortwave (direct plus diffuse solar radiation), upward shortwave (reflected), downward longwave (emitted from different levels of the atmosphere), and upward longwave (emitted from the surface). On a global annual average, the radiation budget for the earth's surface is positive, indicating an excess of solar heating over longwave loss, and is approximately 100 watts per square meter. Instantaneous values, however, may be positive or negative, and range through many hundreds of watts per square meter. In the annual global mean, the positive surface radiation budget is assumed to be matched equally by a negative atmospheric radiation budget so that the planet as a whole is in radiative equilibrium.
Industry:Weather
The tangential force acting at the interface between a liquid and air (or, more correctly, its own vapor) caused by the difference in attraction between liquid molecules and gaseous molecules. Expressed either as a force per unit length of interface or as an energy per unit area of interface.
Industry:Weather
A measure of sunspot activity, computed from the formula ''R ''= ''k''(10''g ''+ ''f''), where ''R'' is the relative sunspot number, ''f'' the number of individual spots, ''g'' the number of groups of spots, and ''k'' a factor that varies with the observer's personal equation, the seeing, and the observatory (location and instrumentation).
Industry:Weather
