Weather and Climate

Weather and Climate are two terms that can easily be mistaken as one in the same, however they are not. Weather refers to what is happening right now and climate is what can be expected or in other words the average weather in a given location over a period of time. Growing up near Yellowstone National Park it can be safely said that the climate and weather are relatively ‘unpredictable’. This can be attributed to a few key features in Yellowstone National Park including its Altitude and its large surrounding Mountain Ranges.

 As you can see in the above image Yellowstone has many varying elevations. We can see the tall mountain peaks, the hills and the lake. There are also many Valleys throughout the Park that we are unable to see through this image. The varying altitudes can give very good insight into the unpredictability of the weather and climate.

Image courtesy of Google Images

            Yellowstone National Park has altitudes ranging from 5,000-11,000 feet above sea level. Yellowstone Lake sits at 7733 feet in elevation but the Park has high mountains and low valleys that make the climate so unpredictable. Lower elevations remain at milder temperatures however can still vary significantly. During summer, (June-September) temperature can range from below freezing to highs around 80 degrees Fahrenheit. Spring and fall temperatures can range from lows in the teens to highs of about 30-60 degrees Fahrenheit. Coldest of all in the winter months temperatures range from well below zero to 20 degrees Fahrenheit. This is due to atmospheric pressure changes as you increase in elevation the pressure of the air around decreases causing the air molecules to expand and move slower. This causes the air to become cooler which can explain why mountains sustain snow much longer than the Valleys.

As described in the image the pressure exerted on the man at a much higher altitude (top of the mountain) is much less than the amount exerted on the man at a much lower altitude (the ground).

Image courtesy of Google Images

  The Rocky Mountains cause much of Yellowstone National Park’s weather including winds and precipitation. As warm moist air from the Valleys collides with the Rocky Mountains it is forced up the windward side of the mountain. When it reaches near the top of the mountain clouds and tiny water droplets are formed causing precipitation. The wind then becomes dry and follows down the leeward side of the mountain in an act referred to as the Chinook Winds. 

The Chinook Winds also greatly attribute to the wide range of temperatures in Yellowstone National Park. As the winds carry over the top of the mountain the air warms. Dry air warms much quicker then moist air which can sometimes cause a rapid increase in temperature of almost 40 degrees. 

Image courtesy of Google Images.

References:

http://clasfaculty.ucdenver.edu/callen/1202/

Lectures: Earth's Temperature and Climate

Weather

Pressure and Winds

http://www.nps.gov/yell/planyourvisit/weather.htm

https://en.wikipedia.org/wiki/Chinook_wind