Light allows humans to see better at night, but did you know light is also a pollutant? Light pollution is a problem that many people aren't aware of. Light being emitted into the atmosphere has many negative impacts on Earth. Accumulating light can damage and modify the behavior of organisms and ecosystems.
There are several light sources that affect organisms. The International Dark-Sky Association (IDA) states that many light sources include building lighting, advertising, commercial properties, offices, factories, street lamps, and illuminated sporting venues. There is so much unnecessary light that it causes light trespass which is best defined as light being positioned in places where it is not intended or needed. A study by “World Atlas of Artificial Night Sky Brightness,” stated that the 99% population of the United States and Europe live under light polluted skies!
This extra light disturbs animals and plants, depending upon the natural darkness of night. Most life forms have cyclic behaviors that typically occur over the course of a 24-hour time span which is referred as a circadian rhythm. Plants, for example, are organisms that most often exhibit this cyclic behavior. By adding artificial light to the night sky, this disrupts the ability of plants to determine when to prepare for winter dormancy, thus increasing the propensity for a more unexpected (or early onset of) death. Sunlight is more powerful, compared to moonlight and artificial light, but artificial light at night can be more powerful than moonlight which is why plants are often more affected by artificial light. This information originated from a study about plants in the “Berkshire Encyclopedia of Sustainability”.
Many types of living organisms are affected by light pollution as well. Nocturnal animals sleep during the day and are active at night. IDA found that light pollution alters their night-time environment by creating the illusion of it being day-time during night-time hours. Some animals that aren’t nocturnal need the darkness of night to survive. Sea turtle eggs are known to hatch at night on the beach. The hatchlings use the phosphorescence by microscopic sea life as a guide to get to the ocean. The phosphorescence appears as a green luminescent glow in the water. Anthropogenic light at night misleads the hatchlings away from the ocean, often resulting in their death. IDA states that in Florida, millions of hatchlings die this way every year.
You would think that because humans are the reason for this emitted light, that it wouldn’t affect them, right? According to the “Berkshire Encyclopedia of Sustainability”, light pollution disrupts sleep for humans as well. Humans produce hormones at night that help our bodies get ready for sleep. Night lighting disturbs a human’s ability to fall asleep which could result in health problems. If we can reduce the amount of emitted light at night, it would be beneficial to many different types of organisms living on planet Earth. (Credit: IDA, the Berkshire Encyclopedia of Sustainability, World Atlas of Artificial Night Sky Brightness)
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© 2018 Weather Forecaster Brittany Connelly
VIV: Verification, Initialization and Verification (Photo Credit: National Weather Service. Process Credit: 26 Operational Weather Squadron)
The central U.S. is no stranger to interesting and sometimes unusual weather patterns, but for those who have been watching, this winter has been unusual to say the least. Arkansas and Missouri went from cold and snowy at the beginning of one week, to tornadoes and warm by week’s end. This brings up the question, how have the forecasters in these locations been doing so well? One of the tools that forecasters use is known as VIV or Verification, Initialization and Verification.
First, it is important to note that any sort of weather models are mathematical algorithms. That is not to state that these models do poorly, it’s quite the opposite in that they are getting better as time goes on. They do, however, need to be checked for accuracy of the product, sometimes one model will work better that then others, sometimes none work well. While each forecaster seemingly has their own take and models they prefer, much of this process remains the same.
The first step of this process is Verification. This stage is checking the model against current weather observations. If the forecaster is looking at a 12 hour model run for winds, they are going to check this against the observations for winds in their given area. The model may be disregarded based on what the current weather pattern is, or adjusted. Whether or not the model is thrown out can, honestly, be situational. For instance, forecasters in Europe would have one or more products that would not handle the position of a cut-off low well. The model would handle winds, temperatures, and clouds accurately, but would want to move the pressure system out of the region sooner than expected. In situations like this, an experienced forecaster would adjust the model for the movement out and continue to use it.
The second part of the process is Initialization. This stage is checking the model against the previous model run. This is primarily to make sure there are not any major discrepancies between the two runs. If any are found and the new model is handling the situation well, the new model can be picking up on things the forecaster could have missed.
The final step is, again, Verification, this is continuing to check the model against current weather observations to make sure it’s still accurate. This part of the process runs similar to the first part, wherein the forecaster can check and see if their forecast is still accurate or if it needs to be amended. The only major difference between this step and the first step is that the final Verification is done every hour.
The VIV process is a handy and important process in every forecaster’s tool belt. Done properly and regularly it can help enhance a forecast and insure a more accurate forecast. This process or one of a similar nature is done for every forecast and has only continued to become more prevalent as model forecasting is becoming more of the norm.
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©2018 Weather Forecaster Kevin W. Owens
DISCUSSION: When looking at a map of the world, many people are often intrigued by the way in which the various landmasses are sized up and positioned around the globe. However, there is often a series of major misconceptions which are held by the general public. The chief illusion is the fact that the respective continents are in fact not accurately represented on most global maps. This is a result of the fact that the globe is an oblate spheroid (i.e., a predominantly round shape) which when laid out as most maps commonly are, the respective continents are inaccurately distorted along a flat surface. Thus, as described in more detail in the brief video attached above, the flat world maps which we always like to look at on our mobile devices or in grade-school are quite inaccurate and misleading. They are misleading because of the way in which given countries and continents are laid out from a flat vs. from a round perspective.
As a result of the world being extended across a Mercator projection, as discussed above, this changes the perspective by which we perceive and are essentially taught to understand the way in which the world is laid out. Therefore, the next time you decide to look at a map of the world, keep the information discussed in the paragraph as well as the brief video attached above in mind when viewing a world map in the future.
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© 2018 Meteorologist Jordan Rabinowitz
We are all familiar with the illuminating reds, pinks, yellows and oranges that grace us every day as the Sun meets the horizon. Many people are enthralled with a good sunrise and sunset, rushing to the beach or the top of a hill to catch one. Many people will go most of their lives in love with the colorful show and wonder what really causes the sky to light up with such vibrant colors.
The colors of a sunset or sunrise is an atmospheric phenomenon associated with light optics. In our atmosphere, air molecules are referred to as selective scatterers because they selectively scatter certain colors of the light spectrum. The scattering of light occurs when light hits the surface of an air molecule and bounces off it in all different directions. The visible light spectrum (light we can see with our naked eye) consists of wavelengths of red, orange, yellow, green, blue and violet with red having the largest wavelength and violet the smallest. Selective scatterers tend to scatter light waves of a shorter wavelength like blue, violet and green. During the day when the Sun is highest in the sky, visible light hits your eyes at a more direct angle and the light has less atmosphere to travel through. Here the Sun appears white as most of the light waves hit our eyes at the same intensity. When the Sun hits the horizon, there is much more atmosphere that the light travels through. As the light travels through that length of the atmosphere, most of the blue, violet and green light is scattered away. The red, orange and yellow light is the what makes it through and reaches our eyes. This is what would make the Sun appear orange and red.
There are also particles in the air that contribute to the color of the Sun at sunset. These particles have a larger diameter than air molecules, thereby scattering the larger wavelengths of light such as yellow. When the atmosphere is filled with more of these particles you can see a redder Sun. For example, salt particles and water molecules are responsible for red sunsets observed over water at a beach.
Sunsets and sunrises are just one of many of the incredible things we are blessed with on Earth. Knowing the science behind them only enhances our admiration. It also makes for a good conversation to have with a friend next time you find each other enjoying one.
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©2018 Meteorologist Alex Maynard