Composition of the atmosphere Discussion of chemistry Layers of the atmosp here (vertical structure)
Meteorology is the science that deals with the atmosphere. For all intents and purposes, meteorology can be said to be the practice of applying the laws of physics and mathematics to the atmosphere in an attempt to describe and predict its behavior.
The professional meteorologist must educate him- or herself heavily with respect to the fundamental principles of mathematics and physics before s etting out to understand the atmosphere.
In Met 1010-03, we will be taking a more qualitative and less quantitative approach to the atmosphere. However, we will occasionally delve into the world of the professional meteorologist and examine som e of the equations they work with based on the fundamentals of mathematics and physics.
In actuality, meteorology is a combination of many sciences, mathematics and physics included. Among just a few of the sciences that are closely related to meteorology are:
| Science | Content |
|---|---|
| Chemistry | The study of matter. The atmosphere is, after all, mat ter. |
| Oceanography | Each day, trillions of tons of water is exchanged between the atmosphere and the oceans and vice-versa. The much- publicized El Nino is just one item of evidence of the dramatic relationship between the atmosphere and the oceans. |
| Geography | Subtle differences in geography, such as mountain ranges, oceans, deserts, lakes, etc. dramatically affect the weather. |
| A stronomy | Studying the atmospheres of other planets and stars can help meteorologists better understand and predict our own atmosphere. |
| Computer Science | The computer programs that meteorologists us e to try and forecast the weather are sometimes over 10 million lines long! Computers are an important part of meteorology and virtually all other sciences. |
| Geology | Meteorologists often attempt to pred ict how much erosion will take place during a particular storm or hurricane or how prone an area will be to flooding given the type of geological environment it is in. This is largely geological. |
In addition to providing your friendly local weather report, the tasks and duties of the meteorologist are many. Although many would concur that one of the primary tasks of the meteorologist is to alert the public of d angerous or life-threatening weather, meteorologists are also involved in a multitude of other duties and projects including:
Meteorology takes place on different time and length scales . The length scales are described below:
Synoptic scale: Refers to meteorology that takes place on the order of 100s or 1000s of miles. Such as frontal systems. high pressure systems, or weather systems that affect large geographi cal land areas.
Example: A cold front that stretches from New England to Florida that is providing New England, the mid-Atlantic states, and the southeast with heavy showers and thunder storms.
Mesoscale: "M eso" from the latin for "middle" scale. Refers to meteorology on the order of 10s to 100s of miles; such as hurricanes, tropical storms, large thunderstorm complexes.
Example: A hurricane, 400 miles in diameter, that moves across the center of the state of Florida.
Microscale: Small scale weather events. Such as isolated thunder- storms, tornadoes, dust devils, waterspouts.
Example: Consider a summertime Tallahassee situation where it is thundering and raining on the FSU campus, meanwhile at the Tallahassee Mall on North Monroe a few miles away, the sun is out and it is dry.
Atomic: On the molecular or atomic scale.
Example: The chem ical Ozone protects us from harmful ultraviolet light by interacting with UV radiation at the molecular level.
Microscale meteorological phenomena can be associated with Mesoscale or Synoptic scale phenomena. Consider a tornado developing in association with a 1000 mile long cold front or a waterspout spawned by a hurricane.
We will cover issues that relate to all 4 of the above scales. We will attempt to start from the smallest and work our way upward to the synoptic scale, b ut in all likelyhoods, we will end up skipping around a bit.
The atmosphere is the "thin 'blanket'" of gases that covers our Earth.
If the Earth were the size of a basketball, the atmosphe re would be about as thick as a sheet of paper. The atmosphere, relative to the size of the Earth, is quite small.
The atmosphere is composed of many different gases, however, the primary gases are nitrogen (78 %), oxygen (21 %), and there are varying amounts of water vapor, argon, carbon dioxide, and methane.
Chemistry is essentially the study of matter. One of its goals is to isolate fundamental particles that al l known substances in the universe are composed of.
Since the atmosphere is composed of matter in varying states and quantities, solid, liquid, and gas, it is good to spend a bit of time discussing the science of chemistry.
Everything you have ever touched, smelled, felt, seen, or had anything to do with is comprised of atoms and molecules. Atoms and molecules are extremely tiny.
Two or more atoms joined together is called a mole cule. In one tablespoon of water alone, there are approximately:
602,000,000,000,000,000,000,000 water molecules!
Think of how many there are in a glass of water? In a pond? In a lake? In the ocean???
You can get the i dea that the building blocks of matter, namely atoms and molecules, are almost incomprehensibly tiny.
(Even Silver here is composed entirely of atoms and molecules)
Believe it or not, as small as atoms are, they too can be further broken down into more fundamental particles. At the center of an atom is its nucleus. In the nucleus are two different types of particles of almost the same size: protons and neutrons. The primary difference between the two is their electric charge. Protons are positively charged and neutrons are neutral.
Circulating around the nucleus are electrons which are much sma ller than neutrons and protons and are negatively charged. Atoms merge or bond together because of electrical attractions between the electrons of one atom and the nucleus of another or others. If you wish to learn more about chemistry, you sh ould strongly consider purchasing an elementary chemistry textbook or scheduling a course in Chemistry.
The nature of an atom is determined by its size - i.e. - the number of neutrons and protons in its nucleus.
The primary molecules i n our atmosphere are nitrogen and oxygen. Our early atmosphere had much more hydrogen and helium, which are the two most abundant atoms in the universe. However, hydrogen and helium are very light and escaped as the Earth's gravitation w as not strong enough to retain them.
Larger planets and stars, such as Jupiter and our sun, have much more hydrogen and helium as they are much bigger and have much stronger gravitational pulls.
In our atmosphere, nitrogen and oxygen are typically referred to as steady- state or long-term gases, as their concentrations do not fluctuate markedly with respect to space and time. Other gases, particularly water vapor, fluctuate greatly. It is this fluctuation of water vapor on Earth that makes meteorology so interesting. The change of phase of water from liquid to solid to gas gives us clouds and precipitation, issues we will be investigating further later in the semester.
Chemistry and discussions pertaining to atoms and mol ecules will appear repeatedly throughout the semester.
As you may have noticed in a swimming pool or in a lake, as you descend deeper, the pressure you feel gets more inte nse. In the atmosphere, the same principle applies. Such that the deepest point of the atmosphere, the surface where we live, the pressure is the highest and it decreases as you travel upward toward the edge of space.
The temperature changes in addition as you ascend upward in the atmosphere. Distinctive layers have been classified in the atmosphere and are described below:
Troposphere: The lowest layer of the atmosphere where most "weather" takes place. Temperature de creases fairly uniformly in the troposphere.
Stratosphere: The level of the Jet Stream. Winds blow very fast. The famous Ozone Layer is found in the Stratosphere. Because of the warming effect of the Ozone Layer , the temp erature actually increases uniformly as you ascend through the Ozone Layer.
Mesosphere: The temperature decreases in this layer.
Thermosphere: The temperature once again increases here as the gases in this layer inte ract with solar particles.
We will study the variation of pressure and temperature with height at length as we progress through the semester.