essentials of meteorology

[...]... weather, we are talking about the condition of the atmosphere at any particular time and place Weather—which is always changing—is comprised of the elements of: 1 air temperature—the degree of hotness or coldness of the air 2 air pressure—the force of the air above an area 3 humidity—a measure of the amount of water vapor in the air 4 clouds—a visible mass of tiny water droplets and/or ice crystals... region Climate, therefore, represents the accumulation of daily and seasonal weather events (the average range of weather) over a long period of time The concept of climate is much more than this, for it also includes the extremes of weather—the heat waves of summer and the cold spells of winter—that occur in a particular region The frequency of these extremes is what helps us distinguish among climates... variety of weather events that we described in terms of weather elements The sum total of weather and its extremes over a long period of time is what we call climate Although sudden changes in weather may occur in a moment, climatic change takes place gradually over many years The study of the atmosphere and all of its related phenomena is called meteorology, a term whose origin dates back to the days of. .. see that half of it is in sunlight, the other half is in darkness The outpouring of solar energy constantly bathes the earth with radiation, while the earth, in turn, constantly emits infrared radiation If we assume that there is no other method of transferring heat, then, when the rate of absorption of solar radiation equals the rate of emission of infrared earth radiation, a state of radiative equilibrium... during April, 1997, inundates Grand Forks, North Dakota, as flood waters of the Red River extend over much of the city Summary worth millions of dollars, and lightning takes the lives of about eighty people in the United States and starts fires that destroy many thousands of acres of valuable timber (see Fig 1.16) Even the quiet side of weather has its influence When winds die down and humid air becomes... the weather by observing certain weather-related indicators Even though many of their ideas were found to be erroneous, the work of Aristotle and Theophrastus remained a dominant influence in the field of meteorology for almost 2000 years The birth of meteorology as a genuine natural science did not take place until the invention of weather instruments During the late 1500s, the Italian physicist and astronomer... this motion is called kinetic energy, the energy of motion The temperature of the air (or any substance) is a measure of its average kinetic energy Simply stated, temperature is a measure of the average speed of the atoms and molecules, where higher temperatures correspond to faster average speeds Suppose we examine a volume of surface air about the size of a large flexible balloon If we warm the air inside,... heat of evaporation (vaporization) Nearly 600 calories* are required to evaporate a single gram of water at room *By definition, a calorie is the amount of heat required to raise the temperature of 1 gram of water from 14.5°C to 15.5°C In the SI system, the unit of energy is the joule (J), where 1 calorie = 4.186 J (For pronunciation: joule rhymes with pool.) The SI system is the international system of. .. range of electromagnetic waves The energy originates from rapidly vibrating electrons, billions of which exist in every object 2 The wavelengths of radiation that an object emits depend primarily on the object’s temperature The higher the object’s temperature, the shorter are the wavelengths of emitted radiation By the same token, *Packets of photons make up waves, and groups of waves make up a beam of. .. electromagnetic spectrum and some of the descriptive names of each region The numbers underneath the curve approximate the percent of energy the sun radiates in various regions Less than 1% 0.001 1 10 100 Wavelength (m) The large ears of a jackrabbit are efficient emitters of infrared energy Its ears help the rabbit survive the heat of a summer’s day by radiating a great deal of infrared energy to the cooler . (the average range of weather) over a long period of time. The concept of climate is much more than this, for it also includes the extremes of weather—the heat waves of summer and the cold spells of winter—that. temperature is the degree of hotness or coldness of the air and, as we will see in Chapter 2, it is also a measure of the average speed of the air molecules. lapse rate in this region of the lower atmosphere. condition of the atmosphere at any particular time and place. Weather—which is always changing—is comprised of the elements of: 1. air temperature—the degree of hotness or coldness of the air 2.