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Social Media: Winter Science
#NWSCitizenScience #CitizenScience

 

Please help the NWS spread these messages on social media! Everyone is welcome to use the text and images provided below to help the NWS build a Weather-Ready Nation.

 

Lake Effect Snow

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Lake Effect snow occurs when cold air moves across warmer water. Warmth and moisture rise into the air, condensing into clouds that can produce 2 to 3 inches of snow per hour or more. Learn more weather science at weather.gov/jetstream

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Lake Effect snow occurs when cold air moves across warmer water. Warmth and moisture rise into the air, condensing into clouds that can produce 2 to 3 inches of snow per hour or more. Learn more weather science at weather.gov/jetstream

What is lake effect snow? Lake effect snow occurs when cold air, often originating from Canada, moves across the open waters. As the cold air passes over the unfrozen and relatively warm waters, warmth and moisture are transferred into the lowest portion of the atmosphere. The air rises and clouds form and grow into narrows bands that produce 2 to 3 inches of snow per hour or more.

 

What's a Blizzard?

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Did you know not all blizzards involve falling snow? By definition, a blizzard includes 35+ mph winds that cause blowing snow, reducing visibility to 1/4 mile or less for at least 3 hours. If the visibility reduction comes from snow that has already fallen, it is called a ground blizzard. Whether or not the snow falls during the time of the blizzard, dangerous conditions can result. Make sure you’re prepared! weather.gov/winter

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Did you know that not all blizzards involve falling snow? Whether or not the snow falls during the blizzard, dangerous conditions can result. weather.gov/winter Be #WeatherReady!

What's a Blizzard? Blowing snow, 35+ mph winds, less than 1/4 mile visibility, for 3+ hours.  Did you know that falling snow isn't necessary for a blizzard?  A blizzard that results from previously fallend snow is called a ground blizzard.

 

Upslope Snow

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Have you wondered why the windward side of mountains or large hills receives so much more snow than surrounding areas? This is due to upslope snow. When moist wind blows against the side of mountains/hills, the air is forced to rise (called orographic lift). As the air rises and cools, water vapor condenses, resulting in clouds and precipitation over the windward region. Conversely, the leeward side often receives less snow due to descending air.

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Why does the windward side of mountains or large hills receive so much more snow than surrounding areas? It’s because of the upslope effect. When you’re in one of these windward areas, make sure you’re #WeatherReady

Upslope Snow: 1) When wind blows against mountains or hills, it is forced to rise. This is called orographic lift. 2) As moist air rises and cools, water vapor condenses, resulting in clouds and precipitation. 3) This results in the windward sides of mountains and hills receiving more snow than surrounding areas in the winter.

 

Snow Water Cycle

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During winter months, falling snow serves as an important source of fresh water across the world. When spring arrives, melting snow helps replenish rivers, lakes, and reservoirs. The melting snow adds much-needed moisture to the soil and helps refill underground aquifers, which are vital for growing crops and for drinking water. weather.gov/jetstream/hydro

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During winter months, falling snow serves as an important source of fresh water. weather.gov/jetstream/hydro

Snow Water Cycle: The hydrologic cycle involves the continuous circulation of water in the Earth-Atmosphere system. At its core, the water cycle is the motion of the water from the ground to the atmosphere and back again. During the winter months, falling snow serves as an important source of fresh water across the world. When spring arrives, melting snow helps replenish rivers, lakes and reservoirs. The melting snow adds much needed moisture to the soil and helps refill underground aquifers, which are vital for growing crops and for drinking water.

 

What Causes Winter?

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Did you know that in the northern hemisphere, winter actually occurs when the Earth is closest to the Sun? This is possible because of the way the Earth tilts on its axis. During winter, the northern hemisphere is tilting away from the Sun, causing the Sun’s rays to hit the northern hemisphere at a lower angle, which results in far lower temperatures. Learn more at scijinks.gov/earths-seasons/

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In the northern hemisphere, winter actually occurs when the Earth is closest to the Sun. Learn more scijinks.gov/earths-seasons/

What Causes Winter? In the northern hemisphere, winter actually occurs when the Earth is closest to the Sun. This is because the northern hemisphere is tilting on its axis away from the Sun.

 

Science of Snowflakes

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Did you know that while no two snowflakes are exactly the same, they are all six-sided? Snowflakes’ hexagonal shapes are due to the molecular structure of ice. Learn more about the science behind snowflakes: noaa.gov/stories/how-do-snowflakes-form-science-behind-snow

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Did you know that no two snowflakes are alike, but they are all 6-sided? noaa.gov/stories/how-do-snowflakes-form-science-behind-snow #SnowflakeScience

Science of Snowflakes: No two snowflakes are the same, but they are all six-sided. Their shapes are due to the molecular structure of ice.

 

Weird Weather (Video)

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Haboobs, ice pillars, and water spouts; oh my! Check this video out for an explanation of each, and then visit weather.gov/owlie/weird-weather for more “weird” weather phenomena. youtu.be/vuk6gvq7Nwk #wxscience

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Haboob. Funny name, dangerous weather phenomenon. Learn about them and other examples of weird weather in this short video: youtu.be/vuk6gvq7Nwk #wxscience

 

What is a 500-year flood? (video)

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"500 year flood" refers to the fact that a flood of that magnitude has a 0.2% chance of occurring in any given year - whether or not one had occurred the year before. The term doesn’t necessarily mean it’s only going to happen one time every 500yrs. youtu.be/eQFyaXDH42U

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"500 year flood" refers to the fact that a flood of that magnitude has a 0.2% chance of occurring in any given year - whether or not one had occurred the year before. The term doesn’t necessarily mean it’s only going to happen one time every 500yrs. youtu.be/eQFyaXDH42U

 

Science of River Flooding

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Water is essential for life on Earth. But in large enough quantities, the very substance we drink and use to grow crops can destroy homes, businesses, and lives. Learn about the science of river flooding in the infographic below, and visit weather.gov/jetstream/flood for more.

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Water is essential for life on Earth. But in large enough quantities, the very substance we drink and use to grow crops can destroy homes, businesses, and lives. Learn about the science of river flooding in the infographic below, and visit weather.gov/jetstream/flood for more.

SCIENCE OF RIVER FLOODING -
Water is essential for life on Earth. But in large enough quantities, the very substance we drink and use to grow crops can destroy homes, businesses and cause fatalities.

River flooding occurs when river levels rise & overflow their banks or the edges of their main channel and inundate normally dry areas.

River flooding can be caused by heavy rainfall, dam failures, rapid snowmelt and ice jams.

Six Steps to Create a River Model
Hydrologic Cycle: Hydrologists try to understand and simulate the natural hydrologic cycle, which is the intricate combination of many processes such as evaporation, transpiration, precipitation, infiltration, interflow, groundwater storage, and runoff.

Precipitation: Precipitation is the primary input to basin hydrologic processes and serves as the primary driver of hydrologic models. Accurate representation of precipitation input is an important intial step. Small river channel systems are very sensitive to rainfall.

Runoff: The next step is to compute the amount of precipitation that appears in surface water within a relatively short time from the onset of a storm event. This is runoff. Runoff consists of 3 components: 
overland flow, rain falling directly on surface water bodies, and interflow.

Unit Hydrograph: After computing basin runoff, the next step is to calculate a forecast hydrograph in units
of discharge. A hydrograph is a plot of the change of stage or discharge with respect to time. Discharge is the volume of water flowing past a location per unit time and is usually expressed in cubic feet per second (cfs).

Streamflow Data: Scientists use streamflow measurements to capture the vital relationship between discharge (volume flow rate) and stage (height) for a given location. This can only be done by taking streamflow measurements at different river levels and noting the corresponding stages. This relation is called a rating curve.

Routing: Hydrologists analyze and interpret how the water moves once it’s in the river and how a flood wave is modified due to the effects of storage and friction as it moves downstream. So, what happens upstream affects the entire downstream community. 

 

Aurora Colors

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The aurora borealis is usually green in color, although it can also appear to be a range of other colors, including red, blue, pink and purple. The color of the aurora is determined by the altitude in which it appears. Different atmosphere compounds (like Nitrogen and Oxygen) are found at different altitudes. When charged particles from the Sun enter our atmosphere, they interact with those compounds, and the aurora is the visible result. Depending on which compounds are being excited by the Sun’s charged particles, different colors will result. Learn more at pwg.gsfc.nasa.gov/polar/telecons/archive/PR_E-PO/Aurora_flyer/aurora-flyer_p2.doc.pdf

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Changing colors of the aurora? It’s elemental, my dear Watson!! The color of the aurora is determined by the altitude in which it appears, as different atmospheric compounds (like Nitrogen and Oxygen) are found at different altitudes. More here: pwg.gsfc.nasa.gov/polar/telecons/archive/PR_E-PO/Aurora_flyer/aurora-flyer_p2.doc.pdf #SpaceWeather

Why does the aurora change colors? The aurora is usually green, but it can be other colors too. The color is determined by the altitude of the aurora. Atmospheric compounds influence the color.

 

Science of Frost Formation (Video)

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Did you know that frost can form when the official low is above freezing? The official temperature is recorded around 6ft above the ground, and in a strong temperature inversion on a clear night, ground temps can be 5-10℉ cooler than the air below that. youtu.be/HBn1oSWu2nE

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Did you know that frost can form when the official low is above freezing? The official temperature is recorded around 6ft above the ground, and in a strong temperature inversion on a clear night, ground temps can be 5-10℉ cooler than the air below that. youtu.be/HBn1oSWu2nE

 

Science of Valley Fog

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Why do we see fog in valleys more often than other spots? First, air at higher elevations cools down, which then drains downslope into the valley. From there, a cool, stable layer forms near the ground, which limits turbulent mixing and traps the cool, moist air. Finally, the air near the ground continues to cool until water vapor molecules are changed into small droplets of liquid water. weather.gov/safety/fog-mountain-valley

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Looking down on the clouds? Do you know how valley fog is created? weather.gov/safety/fog-mountain-valley #FogScience

1. Air cools at higher elevations as the ground radiates heat into the atmosphere and space. 2. Cooler air drains downslope into the valley. 3. A cool, stable layer forms the ground, which limits turbulent mixing and traps the cool, moist air.  4. The air near the ground continues to cool until water vapor moleculesd are changed into small droplets of liquid water.

 

Science of Fog Formation (video)

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Fog limits visibility, delays air travel, brings danger to the roads, and makes things generally spooky. But, how does it form? Watch this short video: youtu.be/QkRqjcO1ROk

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Fog limits visibility, delays air travel, brings danger to the roads, and makes things generally spooky. But, how does it form? Watch this short video: youtu.be/QkRqjcO1ROk #FogScience

 

Science of Wind (Video)

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Wind is just air moving somewhere else...but WHERE is it going, and WHY? Check out this short video for a primer. youtu.be/kb9oRYUzlwQ

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Wind is just air moving somewhere else...but WHERE is it going, and WHY? Check out this short video for a primer. youtu.be/kb9oRYUzlwQ #WindScience

 

Science of Wind Chill

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In calm winds, our body is able to keep a thin layer of warmer air near it. Once the wind picks up, that layer is quickly disrupted, exposing any unprotected body parts to the full brunt of the cold.
Arctic air + brisk winds = dangerously cold wind chills.
weather.gov/safety/cold weather.gov/safety/cold

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In calm winds, our body is able to keep a thin layer of warmer air near it. Once the wind picks up, that layer is quickly disrupted, exposing any unprotected body parts to the full brunt of the cold.
Arctic air + brisk winds = dangerously cold wind chills.
weather.gov/safety/cold weather.gov/safety/cold

Infographic - The Science of Wind Chill. The average temperature of the human body is 98.6 degrees fahrenheit. Under calm conditions, the body radiates heat, creating a layer of warmth between or skin and the cold surroundings.  But when it's windy, the moving air breaks up this insulating layer. It speeds up heat loss by whisking away the warmth from our skin. Hypothermia begins when our body temperature drops two to four degrees.

 

Science of Santa Ana Winds

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Santa Ana winds are strong downslope winds that blow through the mountain passes in Southern California. They are created over the Great Basin region from high-pressure air masses, which then blow down towards sea level. These winds, which can easily exceed 40 miles per hour (18 m/s), are warm and dry and can severely exacerbate brush or forest fires, especially under drought conditions. For more info, visit earthobservatory.nasa.gov/NaturalHazards/view.php?id=10727.

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Santa Ana winds are notorious for creating dangerous fire conditions. Learn how here: earthobservatory.nasa.gov/NaturalHazards/view.php?id=10727 #WindScience

What are Santa Ana Winds? Strong downslope winds. Created over the Great Basin from high-pressure air masses. They are warm, dry, and can worsen forest fires.

 

Skywarn

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Help keep your community safe by volunteering to become a trained storm spotter and learn:
*Basics of thunderstorm development
*Fundamentals of storm structure
*Identifying potential severe weather
*How to report information
*Basic severe weather safety
nws.noaa.gov/skywarn/

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Help keep your community safe by volunteering to become a trained storm spotter and learn:
*Basics of thunderstorm development
*Fundamentals of storm structure
*Identifying potential severe weather
*How to report information
*Basic severe weather safety
nws.noaa.gov/skywarn/

NWS Skywarn: National Weather Service Citizen Science

 

CoCoRaHS

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Ever wanted to take rain or snow measurements? Join CoCoRaHS or Community Collaborative Rain, Hail, and Snow Network. This volunteer network of all ages measures precipitation from their backyard. Data is used by NWS meteorologists to help with forecasts. www.cocorahs.org

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Ever wanted to take rain or snow measurements? Join CoCoRaHS or Community Collaborative Rain, Hail, and Snow Network. This volunteer network of all ages measures precipitation from their backyard. Data is used by NWS meteorologists to help with forecasts. Cocorahs.org #CitizenScience

CoCoRaHS: National Weather Service Citizen Science

 

mPING

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Check out mPING (Meteorological Phenomena Identification Near the Ground) project. Weird name, cool app! You can report the type of precipitation you see where you are. No need to measure! Use the free mobile app to send reports anonymously. Reports are automatically recorded into a database, which improves weather computer models. The information is even used by road maintenance operations and the aviation industry to diagnose areas of icing. mping.nssl.noaa.gov

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Check out mPING (Meteorological Phenomena Identification Near the Ground) project. Weird name, cool app! YOU can report the type of precipitation you see where you are with no need to measure! Use the free mobile app to send reports anonymously. mping.nssl.noaa.gov

mPING: National Weather Service Citizen Science

 

COOP

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The NWS Cooperative Observer Program (COOP) is truly the Nation's weather and climate observing network of, by and for the people. With over 8,700 volunteer observers, this program has existed since 1890 and is one of the few programs that measures snowfall and its water equivalent. Help NWS Citizen Science and become a COOP! You can help support warnings, forecasts, and build a climatological database! For more information, visit weather.gov/coop/Overview

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Join NWS COOP! The NWS Cooperative Observer Program (COOP) is truly the Nation's weather and climate observing network of, by, and for the people. Help support warnings, forecasts & build a climatological database! weather.gov/coop/Overview #NWSCitizenScience

NWS Cooperative Observer: National Weather Service Citizen Science