What is the cause of strong winds? Photo: wwwuppertal The wind is simply air in motion, flowing from high atmospheric pressures to low pressures. Moving anything requires a force. Strong winds are due to a strong pressure gradient force. A… More
What are the plant hardy zones and how do they relate to climate? USDA If you are involved with gardening, you probably are aware of the hardy zones listed on seed packets. The U.S. Department of Agriculture developed the zones… More
Will the 2010 volcanic eruption in Iceland lead to a change in global weather patterns? 2010 eruption of Eyjafjallajökull by Sverrir Thorolfsson No. While the eruption certainly has had impact on aviation and the weather of the immediate area, the… More
What are those beams of light that emerge from clouds?
What is the status of the ozone hole?
How long have satellites been used to study Earth’s weather? NASA image of Explorer VII satellite, 1964 The first successful meteorological experiment conducted from a satellite was launched on Explorer VII on October 13, 1959, just over 50 years ago.… More
Before 1960, the idea that a reasonably accurate two-day weather forecast could be made routinely was a pipe dream – now it’s a routine reality. In fact, it was not until just after World War I that a theory concerning the structure, life cycle and precipitation distribution associated with mid-latitude cyclones, the weather systems that bring snow and rain to Madison, was first proposed by a group of Norwegian scientists, led by Vilhelm Bjerknes, an ambitious but professionally frustrated physicist. More
How accurate are weather forecasts? Image: NOAA In general, weather forecasts are getting better, due to improvements in computer models, observations and our understanding of atmospheric. Accuracy depends on the purpose of the forecast and how far out it extends.… More
Is there a relationship between sun spots and climate? 12th century sunspot drawing, from NASA. Since the invention of the telescope in the 1600s, observers have recorded variations in the numbers of dark spots – “sunspots” – on the Sun’s… More
A radar unit consists of a transmitter and a receiver. The transmitter emits pulses of microwaves, a type of radio waves, outward in a circular pattern. Precipitation scatters these microwaves, sending some energy back to the transmitter, where it is detected by the radar’s receiver. The intensity of this received signal, called the radar echo, indicates the intensity of the precipitation. Measuring the time it takes for the radio wave to leave the radar and return tells us how distant the storm is. The direction the radar is pointing locates the storm. More