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Dramatic seasons, harsh temperatures and impressive winds all help make the South Pole one of the most interesting weather locations on Earth.
If you've never visited a polar destination, you're probably wondering what you can expect weather-wise when you travel to Antarctica. Even if you've spent time in the Arctic Circle, the Antarctic is an entirely different experience. The high elevation and large landmass makes the south pole significantly colder than the north. Of course, temperature is only one piece of the antarctic weather puzzle. Here's an overview of what weather conditions are like on Earth's southernmost destination: Seasons in AntarcticaAntarctica only has two seasons: summer and winter. Because it's located in the southern hemisphere, Antarctica's summer is from October to February. During this time, the sun is almost always in the sky. Days rapidly get longer there in summer, until, eventually, the sun doesn't set at all. This phenomenon is called the Midnight Sun. Although there are multiple places in the northern hemisphere that experience this perpetual sunlight during half of the year, Antarctica is the only southern location where it can be seen. January is the warmest month in Antarctica, during which average temperatures climb all the way up to 0 degrees in the Antarctic Peninsula. However, the average temperatures ranges from -10 degrees celcius to -60 degrees, depending on how far into the continent you travel. If anyone is in Antarctica once winter comes, they're staying until summer returns. Flights and ships cease travel to and from Antarctica once the weather starts to turn, as conditions become too treacherous for travel. Typically, researchers are the only people who brave the antarctic night. This is a valuable time for astronomers, who can use the complete darkness to get spectacular views of the universe. Climatologists are also busy during this time of year tracking and comparing the temperatures on and below the continent's surface.
If you choose to go on an Antarctica cruise in February or March, you will be seeing the continent during its late summer period. This provides a variety of benefits, including the ability to explore more thoroughly as the ice melts and breaks apart, allowing for a high chance of seeing whales on the Peninsula. Late summer is the best time to see whales in Antarctica. It is most common to see humpback whales, minke whales and killer whales, though it's possible to see many other species as well. These can include blue whales, fin whales, sei whales, southern right whales and sperm whales. By March, those adorable penguin chicks are growing up. They begin to fledge and grow into their adult feathers, while their parents may already have gone out to sea to begin to prepare for their own molting season. Why go during this season?If you're an explorer who wants to see as much of Antarctica as possible, choose a late-summer cruise. As the polar ice melts, you'll have access to points much farther south than you would during other travel seasons. You will certainly see some wildlife, as well, and will get to know the untouched majesty of Antarctica in this particular form.
If you think of the Antarctic continent as a constant mass of furious snow storms, think again. While blizzards do happen in the south pole, they're few and far between, and they're typically due to winds blowing lose snow rather than new snow falling. Snow doesn't fall fresh very often - the continent only gets an average of 2 inches of precipitation each year. Antarctica is technically a desert, and a particularly dry one at that. This is because the cold air simply can't hold much water. There's no precipitation without humidity, and there's no humidity without heat. You might be wondering why the continent is covered in snow if it rarely falls. Even though there isn't much precipitation per year, the temperatures don't rise high enough for the snow to melt away. Anything that does fall gets accumulated until it's packed into ice. WindThe dramatic elevation differences throughout Antarctica lead to impressive and harrowing wind speeds. The continent's coastal regions experience what's known as katabatic winds, or winds that that flow down slopes to the areas below. These gusts come roaring through the flatter, lower parts of Antarctica, and regularly reach up to 100 km/h. Although that's the average, the air can - and does - move a whole lot quicker. It's not unusual to see speeds up to 160 km/h, and the highest wind speed ever recorded on the continent was 320 km/h. Interestingly, the south pole's high elevation means it doesn't get particularly high winds itself - the average wind speed there is only about 19 km/h.
Winter in Antarctica, it is dark all of the time. In the Antarctic summer, (between January and March, when there is plenty of daylight—twenty-four hours a day! In September, the Sun rises, and then doesn’t set again until March. Why does Antarctica have six whole months of darkness in the winter and six whole months of lightness in the summer? In most places on Earth, there are daily changes in light—light all day and darkness all night. These daily changes occur because Earth rotates on its axis, spinning once around in roughly twenty-four hours—slow enough so that we don’t get dizzy. For part of that time, the period we call daytime, a given place on Earth, such as your town, faces the Sun. For the remainder of the twenty-four-hour rotation, the period we call nighttime, Earth has turned, and that same area is on the side of Earth facing away from the Sun. So why do we have changes in daylight over the course of the year? Annual changes in light patterns are tied to the seasons There are two reasons that we have seasons. First, Earth’s axis is tilted. Second, Earth revolves around the Sun once every 365 days. Our Earth follows an elliptical path on its journey around the Sun. An ellipse is a slightly flattened circle; this means that there are two extreme points on the orbit, one closest to the Sun and one farthest. (The perihelion is the point where the Earth is closest to the Sun; the aphelion is the point where the Earth is farthest from the Sun.) You might think seasons are caused by Earth’s changing distance from the Sun, with the closest, hottest point being summer and the farthest, coldest being winter. Not so! In fact, winter in the Northern Hemisphere occurs at the perihelion, when the Earth is closest to the Sun. It’s not the Earth’s distance from the Sun that causes seasons, then. So what does? The actual reason for seasons has to do with the tilted angle of the Earth’s axis. No matter how close or far the Earth is to the Sun, it always maintains the same angle on its axis; in other words, it’s always tilted the same way. This means that for part of the path around the Sun, the Southern Hemisphere is tilted toward the Sun, and for part of the path, it is tilted away from the Sun. When it is tilted toward the Sun, the Southern Hemisphere receives a greater amount of sunlight; this occurs in the Antarctic summer. When it is tilted away from the Sun, the Southern Hemisphere receives less sunlight; this occurs in the Antarctic winter. The seasons occur at opposite times in the hemispheres; when the Southern Hemisphere is tilted toward the Sun, the Northern Hemisphere has to be tilted away from the Sun. Antarctica, in the very bottom of the Southern Hemisphere, gets more sunlight and warmth, experiencing summer, when the North Pole is receiving less light and warmth and experiencing winter. Eventually (about six months later), the North Pole is exposed to the incoming light and warmth of summer, and the South Pole is in the darkness of winter. The amount of sunlight received, then, creates the season; an area of the globe is experiencing summer when it is receiving more sunlight for longer periods. This is all very nice, you might be saying…. but WHY does Antarctica have such extremely long periods of light and dark?! Why does the Sun rise only once when the Antarctica summer begins and then set only once when the Antarctica winter begins? Why does the summer day and winter night last for almost six months each? Look again at the drawings of the seasons. During the Southern Hemisphere summer, the Earth is tilted in a way that exposes most of the Southern polar region to the sun’s rays all the time. Even though Earth is rotating daily on its axis, the bottom of the Earth is always tilted toward the Sun. Six months later, at the other end of Earth’s yearly revolution around the Sun, the tilt of the Earth’s axis causes the Southern Hemisphere to tilt away from the Sun all the time. Now, even though the Earth is rotating daily on its axis, the bottom of the Earth is always tilted away from the Sun. At this time, the South Pole gets no sunlight, while the North Pole soaks up twenty-four hours a day of sunlight. At latitudes greater than 6633′, the position of the Arctic and Antarctic circles on our globe, days of constant darkness or light can occur. (The South Pole is at 90S.) Much of Antarctica lies between 6633′ and 90S. As you get farther from the Pole, there are increasing (but still very short) periods of sunlight during winter and darkness during summer. Only the Antarctic Peninsula, sticking out north of ~66S, does not experience twenty-four-hour days in summer or twenty-four-hour nights in winter. (This might help explain why flowering plants are found only on the Peninsula.) But even at the Peninsula, the lengths of summer days and winter nights are vastly exaggerated compared to what most of us experience at home in lower latitudes. |
What season is the Southern Hemisphere experiencing when the South Pole has several months of darkness?
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