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Light Pollution and Aquatic Life March 11, 2009

Posted by linta in Effects.


When you first learned about ecosystems in your primary school, what was the example that your science teacher gave you? At least in our region, the most common example of an ecosystem that is widely used is that of a pond. In fact, water resources are perfect examples of ecosystems. However, today, most water resources are being contaminated due to pollution which lead to the destruction of the ecosystem. Now, let’s see what role light pollution has in destroying aquatic ecosystems.

As you know, light is essential for the growth of plants. Then, what happens if the intensity of light increases? The algal growth increases. This will cause the increased number of alga in the water source which result in the overconsumption of the available oxygen leading to the death of other aquatic organisms. Also, the life cycles of different species are also severely affected by light pollution. For example, due to light pollution, the reproductory phase of some fish species is being altered, affecting their natural behavior. Moreover, it is seen that some fish species are attracted towards light which makes it easier for the fishermen to catch them.


Where is the Milky Way? March 10, 2009

Posted by linta in Effects.


                     Didn’t your mother showed you the bright band of stars shining in the night sky while she was feeding you? My mother did. Whenever we threw away her hands and ran without eating food, she caught us(my sister and me) and pointed at the long star band along with the shining moon. Then I didn’t know what it was but today I am aware that it was the Milky way, our galaxy. Can you figure it out today? I think, the mothers in my place are also having trouble in feeding their babies because the sky no more possesses the scattered pearls, the stars, in its lap. Isn’t that sad? Is this sad only for us? No, there is another group of people who are perhaps the most severely affected- they are astronomers. One who knows what light pollution is can easily understand how it affects astronomy. As the night sky glows as a result of the extra light spilled into it, stars will not be seen clearly. During day time sun hides the stars and at night artificial light does the same. This makes it difficult for astronomers to observe the night sky and take photos.  Also, due to the over illumination of night sky astronomers are having a hard time making light spectra which are helpful in discerning different elements present in galaxies.  

Image source: http://www.nrm.se/images/18.5fdc727f10d795b1c6e800070492/Milky+Way+light+pollution+September+2006.png

Let’s Reveal the Consequences on Wildlife March 5, 2009

Posted by linta in Effects.

les-vegasWe have been talking about environmental conservation and ecological balance in our classes for so long. What we have seen so far is that pollution, global warming, climate change, habitat destruction and deforestation are the major reasons behind the ecological imbalance that we are witnessing today. However, how many of you know that light pollution is a major cause behind ecological imbalance?

The artificial light that is spilled out into the atmosphere affects the behavior of many species. It has been found that polarised light confuses the animals. Most animals come towards glass walled buildings thinking that they are water sources and some insects lay their eggs on substances like asphalt that look like water. Also, it is proved that animals’ reproduction cycles are affected by light pollution too. Isn’t it obvious now that light pollution is much more than the absence of stars in the sky?

Sources: http://news.bbc.co.uk/2/hi/science/nature/7821298.stm


Why do sea turtles go away from sea? March 5, 2009

Posted by linta in Effects.
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Have you ever seen any sea turtles? These cute animals are found in all oceans other than the Arctic Ocean. Now, what about them? As you might have already expected, they are among the species affected by light pollution. Do you know that sea turtles lay their eggs on the coast? After laying the eggs, they bury them in soil and leave them there. After a certain period of time, when the hatchlings come out at night, the parents will not be there to direct them to the ocean. Hence, they move towards the ocean themselves and join their community. At night, the ocean will be glowing due to reflection and refraction of light so they can easily find the way to the ocean.

What happens now is that the coastal regions are also lit because of the fact that we,humans have placed many lights all over the sea coast. This makes it difficult for the baby turtles to find their way to the ocean and they go astray. Imagine we are going away from our parents in our childhood, to a world full of our enemies!

Image source: http://www.cornforthimages.com/galleries/Wildlife/Sea%20Turtles/Green%20Sea%20Turtles/Sea%20Turtle%20at%20Sunset_Kona%20Coast,%20Hawaii.jpg

Birds and Light Pollution March 5, 2009

Posted by linta in Effects.
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bird_hitting_window311Do you know why there aren’t many birds in cities? Is it because they cannot withstand pollution? Is it that they do not have trees to dwell in? Yes, all these reasons contribute to the absence of birds in cities. However, can you believe that part of the reason why birds are less in cities is light pollution? It is amazing,  isn’t it? May be not. As you have an idea about light pollution now, you may have expected to read things like this.

So, how does light pollution affects birds? The main reason is that most birds are diurnal (they are active during day time), so most of them do not leave their nests at night. However, due to light pollution, birds cannot distinguish between night and day. So they come out at night which ultimately leads to their death. You may be wondering how it happens? Well, the most common reason for death of birds due to light pollution is that they fly towards and hit the sky-scrapers in our cities which are lit by numerous lights and die. Also, they do not get enough food because it is difficult to find prays when the place is lit by artificial light. Additionally, don’t be astonished if you hear a bird like cock, which are supposed to sing in the morning, singing at midnight. Now, haven’t you realized how dreadful light pollution is?

image source: http://www.2-boots.com/blog/Likeabird_97F4/bird_hitting_window31.jpg

Link Between Cancer and Light Pollution February 26, 2009

Posted by linta in Effects.

city1Breast cancer is one among the most severe health effects of light pollution. In order to understand the link between the occurrence of breast cancer and light pollution, we should have an understanding of human body. It is a common knowledge that our body produces many hormones which are in fact chemical messengers. Melatonin is such a hormone produced by the pineal gland, the organ which regulates our wake-sleep-wake cycle. Which means this hormone helps the body to keep up a rhythm. The most important fact is that this hormone is suppressed by light and is active in darkness. Researchers have found out that when we are exposed to light at night, melatonin production retards within seconds. Thus this hormone is called “the hormone of darkness.” The function of melatonin that worth noting is that it makes the cancer cells to sleep at night. Which means it regulates the amount of oestrogen(female hormone) secreted. But, when the secretion of melatonin is retarded due to the exposure to light, oestrogen is secreted in large amounts leading to a higher risk of light pollution. This is illustrated by the fact that blind women are 36% less likely than those who are sigheted to be breast cancer patients. It has been observed that light pollution causes not only breast cancer, but also endometrial and prostrate cancers as well.

Sources: http://www.health24.com/medical/Condition_centres/777-792-1461-1671,31149.asp


(image) http://ngm.nationalgeographic.com/2008/11/light-pollution/img/17-toronto-aerial-night-665.jpg

Breast Cancer and Light Pollution February 25, 2009

Posted by linta in Effects.

Why are we so anxious about tackling pollution? Is it because we are awfully concerned about the welfare of our mother nature? Certainly not. We conserve our environment because we are concerned about our own welfare. We protect other animals from extinction because we are aware that the absence of one species harms survival of all other species, including humans, in the ecosystem. We hurry to find ways to deal with global warming and climate change because they are great threats to our very existence. Briefly, our aspiration to lead a healthy and peaceful life is the thing that forces us to conserve the nature. Likewise, light pollution is also a matter of concern because it has been proved that light pollution has serious implications on human health.

The most recent finding regarding the effects of light pollution in human health is that women who are exposed to artificial light are likely to be afflicted by breast cancer. Many studies, examining the relationship between breast cancer and light pollution, have been conducted so far. Let’s consider the study carried out by some epidemiologists in 147 Israeli communities. The study suggests that “when the brightest communities were compared to the darkest communities, the cities with the brightest lights had a 73% higher rate of breast cancer!” which is really appalling. Various studies suggest that those, especially females, who work at night or are exposed to artificial light, are very likely to develop breast cancer. I am not going into the complex scientific explanation behind this occurrence. However, it is really a sad that the reckless activities of human beings make the world a difficult place to live in.

Click the link that follows to have look on a  study examining the relationship between light pollution and breast cancer.    cancer-incidence

Source: http://www.homerglen.org/Environment/Lighting/BreatCancerAndLightPollution.pdf

Light Pollution and Energy Wastage February 23, 2009

Posted by linta in Effects.
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Now that we have seen the causes of light pollution, it is worthwhile to look at the effects. In fact, the effects are not limited to humans, animals are also affected by this phenomenon. However, before knowing how it affects other species, we should know how it affects us, humans. My grandmother is very sensitive to light and it can be said that she is ‘repelled by light’. She prefers sitting in dimness, so when we turn on the electric lights at night, she will go to another room where there is not much light. According to her, our house is more lit at night than it is during daytime. This has often led to small conflicts between my little sister and her. So, here comes the question. Are the effects of light pollution on human lives limited to such conflicts between those who hate light and those who cannot live without light? (Here, light stands specifically for artificial light.) Or are there more consequences that we do not notice?

Well, let’s see. As you have already assumed, light pollution does have some more consequences other than such little conflicts. Today, we will look at one of such effects, which is the wastage of energy. Scientists have been warning us about the future energy crisis due to the overconsumption and the reckless use of energy. The severity of this energy wastage is reflected in the fact that only in the U.S., the energy waste due to light pollution costs more than one billion dollars! Now, think about the globe as a whole. However, this doesn’t mean that we should stop using light at night, but we can still reduce its use. Do we need all these decoration lamps and flash lights that focus light up into the sky? One thing we should keep in mind that while one part of the world is still in darkness without electricity or other means of lighting the night, we are sinking in light! 

 Image URL: http://earthfirst.com/wp-content/uploads/2008/10/light-pollution.jpg