Category Archives: Weather Dangers
The National Oceanic and Atmospheric Administration (NOAA) operates weather satellites with instruments capable of locating fires and determining fire characteristics such as size and intensity. These satellites also are critical to observing and monitoring smoke from those fires.
NASA recently launched a new satellite instrument to monitor air pollution. The Tropospheric Emissions: Monitoring of Pollution, or TEMPO, was launched into geostationary orbit on April 6, 2023. TEMPO measurements join an international satellite constellation of observations that will track pollution around the globe. The instrument measures sunlight reflected off Earth’s surface and solar energy scattered by clouds and the atmosphere. Gases in the atmosphere absorb sunlight at particular wavelengths, and the measured color spectra is used to determine the concentrations of several gases in the air, including nitrogen dioxide. Continue reading
The heat index (HI) indicates how hot it feels.
The HI is calculated using an equation that is a function of air temperature and the relative humidity. The HI is sometimes referred to as the “feels-like” temperature. Continue reading
Fires require something to burn plus air to supply oxygen and a heat source to get the fuel to its ignition temperature.
Once a fire starts, weather is one factor of how it will spread and if it will grow. The important weather factors are temperature, wind and humidity. Warmer temperatures allow fuels to ignite quickly, and low humidity keeps the fuel dry and easy to burn. Wind brings oxygen to the fire and also can help to spread it. Continue reading
Ozone (O3) is a molecule formed by three oxygen atoms.
Ozone that resides in the stratosphere absorbs ultraviolet rays of the sun, protecting life on Earth’s surface from these high-energy electromagnetic waves. O3 also can occur near the ground, where it is considered a pollutant, as it is a chemically reactive gas that can cause respiratory problems when breathed. Continue reading
Light is a form of electromagnetic energy that does not need matter to propagate. We can characterize this energy by its wavelength, which is the distance along a wave from one crest to another. Our eyes are sensitive to light with wavelengths between approximately 0.4 to 0.7 microns. Blue colors have shorter wavelengths, while red colors have longer ones.
When light interacts with particles suspended in air, it can be scattered or absorbed. Energy that is scattered causes a change in direction of the light path. The amount of light that is being scattered is a function of the size of the particle relative to the wavelength of the light falling on the particle. While all colors are scattered by air molecules, violet and blue are scattered most. The sky looks blue, not violet, because our eyes are more sensitive to blue light. Continue reading