AIRS observes El Niño and La Niña
In 2016 a significant El Niño developed in the Pacific Ocean and we can see its effect on Earth's atmosphere in the images below, made with data acquired by the Atmospheric Infrared Sounder on NASA's Aqua satellite and produced by NASA's Jet Propulsion Laboratory.
El Niño is a climate cycle in the Pacific Ocean with a global impact on weather patterns. It's characterized by unusually warm ocean temperatures in the equatorial Pacific, in contrast to La Niña which is characterized by unusually cold ocean temperatures in this same region.
El Niño's effect on Relative Humidity
Storm tracks located in the tropics through the middle latitudes are typically moist, with drier air found in between these storm tracks. The current El Niño has led to higher relative humidity in the eastern tropical and subtropical Pacific, but it's brought much drier conditions to Indonesia and southeast Asia which makes these regions susceptible to drought and fires.
Movie: You can also view a time series of relative humidity anomaly as it moves from February 2015 through February 2016.
EL NIÑO'S EFFECT ON CIRRUS CLOUDS
Cirrus clouds are ice clouds that occur in Earth’s upper troposphere and they are typically found between 6-10 miles in altitude. They are often associated with tropical convection and wintertime storms in the midlatitudes. The change in the pattern of cirrus cloud frequency is similar to the pattern shifts in relative humidity and outgoing longwave radiation. There has been a large increase in cirrus cloud frequency in the eastern Pacific and over the southern-tier of the U.S. and Mexico over the last several months. This is also associated with a more active subtropical jet stream that is very typical of a strong El Niño.
EL NIÑO'S EFFECT ON outgoing longwave radiation
Outgoing Longwave Radiation (OLR) is the thermal radiation, or heat energy, that radiates from Earth's surface and atmosphere and goes out to space. OLR depends on temperature, moisture, and clouds, and it's usually largest over the subtropical desert regions and the subtropical oceans. OLR is lower in the high latitudes and in the cloudy and moist portions of the tropics. El Niño has caused a shift in the regular pattern: there is reduced OLR in the tropical eastern Pacific which causes increased convective storms and moisture, and there is a strong increase in OLR in the tropical western Pacific. This shift in the convection pattern effects on the winter storm track in California and is typical of a strong El Niño.