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Should we stop climate research?
Scientific evidence for slow, ongoing, systematic warming of Earth’s atmosphere is unequivocal. This conclusion comes from evidence-based science and a physical understanding of that evidence. Regular scientific assessments of global and regional climate began in the 1970s. These assessments, along with a physical understanding of the atmosphere, show that the impact of human activities on this warming has evolved from theory to established fact. This is not a radical political statement; it is a firm conclusion based on the analysis of carefully considered observations.
Burning fossil fuels generates greenhouse gases, which are transparent to solar radiation but absorb large amounts of terrestrial infrared radiation that results in warming the atmosphere. The planet’s average surface temperature has risen about 2 degrees Fahrenheit since the late 1800s. Most of that warming has occurred in the past 40 years. Continue reading
How do satellites help forecast the weather?
Satellite data help forecast the weather in two ways: expert forecasters interpret the satellite images and numerical weather-prediction models assimilate the data they collect. Image analysis plays an important role in short-term forecasts, those that predict the weather 1 to 3 hours into the future, while numerical weather predictions are more useful in 12-hour to 3-day forecasts.
While weather forecasters routinely analyze current satellite observations, most data never reach forecasters’ eyes. Most satellite observations are assimilated into numerical weather-prediction models. Today’s weather forecast models rely on satellite data to make accurate weather predictions. These satellite observations include the vertical distribution of temperature and humidity, cloud distributions, land and sea surface temperatures, location of volcanic ash, fires, and wind speeds and directions. Continue reading
What is vapor pressure?
Weather reports often include the dew point temperature and the relative humidity. These are just two of several ways to express the amount of water vapor in the atmosphere. Vapor pressure is another way. Each method has advantages and disadvantages.
Gas molecules exert a pressure when they collide with objects. The atmosphere is a mixture of gas molecules and each type of gas makes up a part of the total atmospheric pressure. The pressure the water molecules exert is another useful method of representing the amount of water vapor in the atmosphere. The pressure caused by these water vapor molecules is called the vapor pressure. Atmospheric vapor pressure is expressed in millibars (mb). Continue reading
What are radiosondes?
Radiosondes are instrument packages that measure the vertical profiles of air temperature, relative humidity, and pressure from the ground all the way up to about 19 miles. These radio-equipped meteorological instrument packages are carried aloft by a helium-filled “weather balloon.” … Continue reading
Why does the severe weather threat increase as spring and summer approach?
As the threat of winter snows recedes across the country, it is replaced by the threat of severe weather (i.e. thunderstorms with hail, damaging winds and tornadoes).
The severe weather season, though broadly spanning March through August across the United States, is actually quite regional. It begins in March in the southern states, moves to the southern Plains during April and May, and then further north toward the Great Lakes states during the summer. Continue reading
Category: Meteorology, Seasons, Severe Weather
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