A devastating series of fires occurred in Southern California during October 2003. The effects of these fires were detectable from space. The Total Ozone Mapping Spectrometer (TOMS) instrument measures aerosol particles (microscopic airborne dust and smoke). TOMS was able to detect aerosols from these fires moving West over the Pacific Ocean and East over the continental United States.

Chlorine monoxide (ClO) in the atmosphere as measured by the Microwave Limb Sounder (MLS) instrument on NASAs Aura satellite. MLS can simultaneously measure several trace gases and ozone-destroying chemicals in the upper troposphere and photosphere. In this series of animations we present chlorine monoxide (ClO), hydrogen chloride (HCl), nitric acid (HNO3), ozone (O3), water vapor (H2O) and temperature measurements. These are first light data taken when the MLS was operated for the first time. ClO is a temporary byproduct of the chemical reaction sequence by which chlorine from chlorofluorocarbons (CFCs) destroys ozone.

Wildfires started by lightning burned more than 80,000 acres in Alaska in June 2004. The effects of these fires can be seen across North America with the Total Ozone Mapping Spectrometer (TOMS) instrument on the Earth Probe spacecraft. TOMS detects the presence of UV-absorbing tropospheric aerosols across the globe.

The Erythemal Index is a measure of ultraviolet (UV) radiation at ground level on the Earth. (The word erythema means an abnormal redness of the skin, such as is caused by spending too much time in the sun--a sunburn is damage to your skin cells caused by UV radiation.) Atmospheric ozone shields life at the surface from most of the harmful components of solar radiation. Chemical processes in the atmosphere can affect the level of protection provided by the ozone in the upper atmosphere. This thinning of the atmospheric ozone in the stratosphere leads to elevated levels of UV at ground level and increases the risks of DNA damage in living organisms.

Hydrogen chloride (HCl) in the atmosphere as measured by the Microwave Limb Sounder (MLS) instrument on NASAs Aura satellite. MLS can simultaneously measure several trace gases and ozone-destroying chemicals in the upper troposphere and photosphere. In this series of animations we present chlorine monoxide (ClO), hydrogen chloride (HCl), nitric acid (HNO3), ozone (O3), water vapor (H2O) and temperature measurements. These are "first light" data taken when the MLS was operated for the first time. Ozone-destroying chlorine (Cl) atoms are neutralized when they bond with hydrogen (H) to form HCl.

The Erythemal Index is a measure of ultraviolet (UV) radiation at ground level on the Earth. (The word erythema means an abnormal redness of the skin, such as is caused by spending too much time in the sun--a sunburn is damage to your skin cells caused by UV radiation.) Atmospheric ozone shields life at the surface from most of the harmful components of solar radiation. Chemical processes in the atmosphere can affect the level of protection provided by the ozone in the upper atmosphere. This thinning of the atmospheric ozone in the stratosphere leads to elevated levels of UV at ground level and increases the risks of DNA damage in living organisms.

Nitric Acid (HNO3) in the atmosphere as measured by the Microwave Limb Sounder (MLS) instrument on NASAs Aura satellite. MLS can simultaneously measure several trace gases and ozone-destroying chemicals in the upper troposphere and photosphere. In this series of animations we present chlorine monoxide (ClO), hydrogen chloride (HCl), nitric acid (HNO3), ozone (O3), water vapor (H2O) and temperature measurements. These are "first light" data taken when the MLS was operated for the first time. Nitric acid is created from the nitrogen oxide emitted by automobiles.

Ozone (O3) in the lower stratosphere and upper troposphere as measured by the Microwave Limb Sounder (MLS) instrument on NASAs Aura satellite. MLS can simultaneously measure several trace gases and ozone-destroying chemicals in the upper troposphere and photosphere. In this series of animations we present chlorine monoxide (ClO), hydrogen chloride (HCl), nitric acid (HNO3), ozone (O3), water vapor (H2O) and temperature measurements. These are "first light" data taken when the MLS was operated for the first time.

Hurricane Isabel generated large amounts of rain over the Atlantic ocean as it approached East coast of the United States in September 2003. In fact, unlike many hurricanes, most of the Isabels rainfall did not occur over land; flooding on land was caused mainly by storm surge. This animation shows accumulation of rainfall from the hurricane--each frame shows the total amount of rain since the start of the measurement period. Rain from other sources has been masked out, so the hurricane track is clearly visible as the storm moves across the Atlantic.

Desert storms in northern Africa raise dust that is carried in the upper atmosphere across the Atlantic Ocean. The dust, which may carry potentially hazardous bacteria and fungi, can land as far west as the Caribbean and the Americas.