Weather can be an engaging topic for children. From understanding blizzard science to the history of snowfall, here are some interesting facts about weather that you can share with them.
Winter brings with it its share of cold outbreaks, but most colds and flu are caused by viruses instead of weather conditions. When people sneeze or cough without covering their mouths or noses they spread these viruses further.
Death Valley
As its name implies, Death Valley National Park can be extremely hot; but why does it seem hotter than other deserts? A variety of factors contribute to its unbearably hot temperatures.
Death Valley stands out among other deserts for a few key factors. First is its long and narrow shape surrounded on all sides by high mountain ranges that create pockets of hot air that radiate nightly. Another key element is the low rainfall; most deserts receive around 6-8 inches annually but Death Valley receives less than two.
Death Valley stands out among other areas with its extremely hot ground temperature, reaching as much as 201 degrees Fahrenheit near boiling point – making this region of California the hottest place on Earth.
Though Death Valley draws tourists with its extreme heat, visitors should remember that its intensity can be deadly if exposed for too long. A number of people have died due to heatstroke or dehydration in recent years – so visitors should avoid strenuous activity during summer when temperatures are at their highest point.
Visit Death Valley can still be an exhilarating experience; temperatures have decreased during fall and winter and conditions are much more comfortable. A car tour is an excellent way to enjoy its sights without overexerting yourself physically.
For an optimal experience of Death Valley, plan your visit during its coolest months. Temperatures remain relatively warm during the daytime but become much more bearable once the sun has set and air temperatures begin to decrease at nightfall. Make sure to pack plenty of water, sunscreen and sunglasses, along with sturdy hiking shoes; additional layers may come in handy at higher elevations as temperatures can dip significantly lower than expected.
The Jet Stream
Jet streams are currents of fast-moving air that encircle Earth at great speed, fuelled by differences between low and high latitudes in temperature as well as Earth’s rotation. Normally, jet streams flow west to east and steer weather systems – low pressure areas – along mid latitudes. One such jet stream, the North Atlantic jet stream is responsible for creating frigid winter conditions across much of northern Europe and America.
However, jet streams do not always follow a straight path – they resemble more like an unpredictable river that meanders back and forth over time, sometimes creating troughs (similar to waves on water) and ridges (like hills). This occurs due to how the Sun heats Earth’s atmosphere: warmer air rises higher up into the troposphere as cooler air sinks lower. Jet streams serve to facilitate this exchange by keeping this exchange of warm and cool air moving efficiently and in an orderly fashion.
So, the jet stream is constantly shifting across vast regions of the earth – this makes it so vital for meteorologists. Its fluctuating movements affect regional patterns of heat and cold, wetness and dryness on very short timescales; therefore making forecasting weather difficult due to this factor alone.
The Polar Jet Stream is our fastest and strongest main jet stream, reaching speeds of 110 miles per hour on average. It typically circles the Arctic region during summertime before speeding back up as it nears equator and passes over Northern Hemisphere in winter.
The polar jet tends to bend north-south due to the planet’s rotation, creating Rossby waves in its path. This phenomenon becomes especially noticeable when the polar vortex breaks apart or weakens, such as what happened in January and February this year when record cold spells hit parts of North America and Canada. Scientists now worry that climate change may cause an increasing frequency in which this occurs resulting in increasingly intense winter storms.
The Polar Vortex
January was a month filled with extreme Arctic air, record-setting snowstorms and wild temperature swings across much of the U.S. While these weather events may simply have been one-off occurrences, experts believe there is a relationship between severe cold temperatures and an unpredictable phenomenon known as the Polar Vortex.
Polar vortices might sound like something out of a Marvel superhero film, but in reality, they’re real physical structures found over the North Pole. Enclosed within this low pressure cone sits an area known as the Polar Jet Stream that circles roughly six to 30 miles above ground (half way between Earth and moon). While normally strong and focused in the Arctic region, its strength can sometimes weaken or even dissipate completely, allowing polar vortexes to travel further south than previously expected.
When the polar vortex is functioning at its best, it prevents Arctic air from penetrating mid-latitude regions of North America and Europe. But when its strength wanes, Arctic temperatures can push further south, leading to extreme winter weather events.
Scientists still can’t fully explain what causes the Polar Vortex to shift in strength and direction, though many suspect that its movements could be linked with fluctuations in atmospheric temperatures – also known as climate change.
As the Arctic warms, its winds become less stable, making it easier for the polar jet stream to push it southward. This happens because warmer air in lower atmosphere tends to create larger atmospheric waves with more peaks and troughs than normal, thereby weakening its hold over polar vortex winds.
As larger waves travel across the polar jet stream, they cause it to weaken and change direction, breaking apart its polar vortex and allowing cold air to push further south, often with accompanying storms of bitterly low temperatures. Such was the case this January and February when an irregularly weak polar vortex funneled Arctic air directly into cities from Fargo to Pittsburgh to Detroit; school closures, flight cancellations, mail deliveries halts were common as a result of its effects.
The Cold Blob
AMOC (Atlantic Meridional Overturning Circulation) is an integral component of Earth’s climate system, controlling how much heat travels across ocean surfaces and depths. This complex nonlinear system can be affected by small differences in temperature or salinity that alter water density across its surfaces or depths, which plays an essential role.
As our planet warms, scientists have noted a decline in AMOC. This has allowed bone-chilling Arctic air – usually held back by jet stream currents – to leak far farther south. Furthermore, glacier retreat has contributed significantly to sea level rise.
The cold blob is an oddity on the ocean’s surface that’s clearly visible on recent NASA maps. It defies all explanation because its appearance runs counter to global warming trends despite humans having contributed enormous amounts of heat energy into it.
In this instance, weakening of AMOC may have contributed to the cold blob’s formation; however, further research will need to confirm this hypothesis. A growing body of research has demonstrated how AMOC plays a vital role in controlling how much heat travels from surface waters into deeper ocean waters; its function can be affected by natural and man-made factors alike including El Nio events and volcanic eruptions.
As warm water flows from the Gulf Stream near North America and east into the North Atlantic Current, it travels over an area known as a cold blob where its heat releases into colder waters below, creating chilling effects in these deeper bodies of water. When these deep, cold waters return back towards tropical regions they often lead to tropical storms being created.
Cold blob temperatures have caused an increase in convection and subpolar mode water formation, helping to cool the ocean surface; however, this means the North Atlantic region is more vulnerable to hurricanes and extreme weather events.