Sunday, May 17, 2009

The Enlightenment

I watched a show on the History Channel about Ben Franklin (that would be a whole other blog topic–the man accomplished everything). They referred to the time period as The Enlightenment and honestly, I don’t remember ever learning that one. Must have been a “skip” day.

The period known as The Enlightenment refers to the Western philosophy in the 18th century, from around 1740 to 1789, prior to the French Revolution (1789-1799). There were remarkable cultural changes characterized by a loss of faith in traditional religious and political sources of authority and where reason based on democracy, human rights and science was advocated as the primary source for authority. The term Enlightenment was used by writers of the time, aware they were emerging from centuries of darkness and ignorance into a respect for humanity and reason. “Dare to know,” coined by German philosopher Immanuel Kant, was the motto of the age. The period is also referred to as the Age of Reason.

The signatories of the Declaration of Independence, including Ben Franklin, were motivated by the principles of Enlightenment, which were based more on a set of values and not on ideas or shared beliefs. The Bill of Rights, the French Declaration of the Rights of Man and of the Citizen, and the Polish-Lithuanian Constitution of May 3, 1791 were all motivated by the values and principles of Enlightenment.

The precursors to The Enlightenment stemmed from new discoveries in science by Copernicus and Galileo, by philosophical rationalists Descartes and Spinoza, political philosophers Hobbes and Locke and skeptical thinkers such as Bayle in the 17th century. The most important common belief to philosophers and intellectuals of this period were an abiding faith in the power of human reason.

The Enlightenment ended with the French Revolution, which some see the social and political ferment of the period as being responsible for the Revolution. Conservatives believed the Enlightenment was too radical, while romantic writers and artists who came after the period found it to be without passion or soul.

The Enlightenment’s effects on the 19th and 20th centuries marked a decline of the church and growth of modern secularism and served as the model for political and economic liberalism.

Now you’re a little smarter, Girlfriend — And so am I.

Sunday, May 10, 2009

Additive and Subtractive Colors

In my previous research, the explanation behind cloud color (additive color) persuaded me to review the topic again.

Additive Colors — Red, Green & Blue
Additive color systems, such as televisions or computer monitors, start with no light (black). Additive colors are produced by light sources and the wavelengths create color. Red, green, and blue are called additive colors because when two of them are added (mixed), one of the subtractive colors is produced. Combining all three additive colors with equal intensities produces white. Combining all three additive colors with different luminosities reveals the full gamut of colors.

Red + Green + Blue = White
Blue + Green = Cyan
Blue + Red = Magenta
Green + Red = Yellow

Subtractive Colors — Cyan, Magenta & Yellow
Subtractive color systems, such as paint or ink, start with white light. Subtractive colors are produced by light reflecting off of opaque surfaces. Some of the light that strikes the surfaces is being absorbed, or subtracted, by the surfaces and the rest of the light is reflected. The variation in mixtures of wavelengths being absorbed and reflected creates colors. Combining all three subtractive colors with equal intensities produces black, because all colors are subtracted.

Cyan + Magenta + Yellow = Black

Subtract Red, reflect the Green & Blue = Cyan
Subtract Green, reflect the Red & Blue = Magenta
Subtract Blue, reflect the Red & Green = Yellow

Two subtractive colors together produce an additive color because each of the two subtractive colors absorbs (subtracts) additive colors.

Magenta + Yellow subtracts the Green & Blue is seen as Red
Cyan + Yellow subtracts the Red & Blue is seen as Green
Cyan + Magenta subtracts the Red & Green is seen as Blue

Now you’re a little smarter, Girlfriend — And so am I.

Sunday, May 3, 2009

Clouds

I was watching a show and a character mentioned Cumulus clouds. I realized I didn’t remember exactly which ones those were, or any specifics of the cloud types for that matter. Since it was a kid's show and my 4-year-olds were watching, I decided I should brush up on the information. I felt a little dumber than a child, frankly.

The Earth’s troposphere is the lowest level of our atmosphere and this is where clouds hang out. All air contains water. The water in the air near the ground is in vapor form. When warm air rises, it expands and cools. Cool air holds less water vapor than warm air, so some of the vapor condenses onto microscopic dust particles in the air turning into water or ice. The water droplets are so small and light they float in the air. When billions of droplets combine, they become a visible cloud.

Clouds are white because they reflect the light from the sun. The rays from the sun are made up of red, orange, yellow, green, blue, indigo and violet. When you add those colors together, the result is white. Clouds reflect all of the sunlight’s colors the exact same amount, so they appear white.

Clouds are classified by the height of the cloud base. Names beginning with "Cirr" are located at high levels. Alto clouds are found at middle levels. Stratus clouds are at low levels.

High-Level Clouds form above 20,000 feet and since the temperatures are so cold at such high elevations, these clouds are primarily composed of ice crystals. They are typically thin and white in appearance, but can appear in an array of colors when the sun is low on the horizon.

Mid-Level Clouds typically appear between 6,500 to 20,000 feet. Because of their lower altitudes, they are composed primarily of water droplets. They can also be composed of ice crystals when temperatures are cold enough.

Low-Level Clouds are mostly composed of water droplets since their bases generally lie below 6,500 feet. When temperatures are cold enough, these clouds may also contain ice particles and snow.

Vertically-Developed Clouds are commonly generated through either thermal convection or frontal lifting. They can grow to heights in excess of 39,000 feet, releasing energy through the condensation of water vapor within the cloud itself.

Cirrus clouds are the most common of the high clouds. They are composed of ice and are thin, wispy clouds blown in high winds forming long streamers. Cirrus clouds are usually white and predict fair to pleasant weather. By watching the movement of cirrus clouds you can tell from which direction weather is approaching. Cirrus clouds usually indicate that a change in the weather will occur within 24 hours.

Cirrostratus clouds are thin, sheet-like high clouds that often cover the entire sky. They are so thin that the sun and moon can be seen through them. Cirrostratus clouds usually come 12-24 hours before a rain or snowstorm.

Cirrocumulus clouds appear as small, rounded white puffs that appear in long rows. Their small ripples sometime resemble the scales of a fish. Cirrocumulus clouds are usually seen in the winter and indicate fair, but cold, weather. In tropical regions, they may indicate an approaching hurricane.

Altostratus clouds are gray or blue-gray mid level clouds composed of ice crystals and water droplets. These clouds usually cover the entire sky. In the thinner areas of the clouds, the sun may be dimly visible as a round disk. Altostratus clouds often form ahead of storms with continuous rain or snow.

Altocumulus clouds are mid level clouds made of water droplets and appear as gray puffy masses usually in groups. If you see altocumulus clouds on a warm, sticky morning, be prepared to see thunderstorms late in the afternoon.

Stratus clouds are uniform grayish clouds that often cover the entire sky. They resemble fog that doesn't reach the ground. Light mist or drizzle sometimes falls out of these clouds.

Stratocumulus clouds are low, puffy and gray and most form in rows with blue sky visible in between them. Rain rarely occurs with stratocumulus clouds, however, they can turn into nimbostratus clouds.

Nimbostratus clouds form a dark gray, wet looking cloudy layer associated with continuously falling rain or snow. They often produce precipitation that is usually light to moderate.

Cumulus clouds are white, puffy clouds that look like pieces of floating cotton. Cumulus clouds are often called "fair-weather clouds". The base of each cloud is flat and the top has rounded towers. When the top of a cumulus cloud resembles the head of a cauliflower, it is called cumulus congestus or towering cumulus. These clouds grow upward and they can develop into giant cumulonimbus clouds, which are thunderstorm clouds.

Cumulonimbus clouds are thunderstorm clouds. High winds can flatten the top of the cloud into an anvil-like shape. Cumulonimbus clouds are associated with heavy rain, snow, hail, lightning and even tornadoes. The anvil usually points in the direction the storm is moving.

Mammatus clouds are low hanging bulges that droop from cumulonimbus clouds. Mammatus clouds are usually associated with severe weather.

Lenticular clouds are caused by a wave wind pattern created by the mountains. They look like discs or flying saucers that form near mountains.

Fog is a cloud on the ground composed of billions of tiny water droplets floating in the air. Fog exists if the atmospheric visibility near the Earth's surface is reduced to around three quarters of a mile.

Contrails are condensation trails left behind jet aircrafts. Contrails form when hot humid air from jet exhaust mixes with environmental air of low vapor pressure and low temperature. The mixing is a result of turbulence generated by the exhaust.

Green Clouds are often associated with severe weather. They form when the clouds are illuminated by light reflected off green vegetation, such as large cornfields or a heavily wooded forest. In the Great Plains region of the U.S., green clouds are associated with storms likely to produce tornadoes.

Latin Translations
Cumulus — Heap
Stratus — Layer
Cirrus — Curl of Hair
Nimbus — Rain

Now you’re a little smarter, Girlfriend — And so am I.