Climatology is the study of climate
Climate encompasses the statistics of temperature, humidity, atmospheric pressure, wind, rainfall, atmospheric particle count and other meteorological elemental measurements in a given region over long periods...

, scientifically defined as weather conditions averaged over a period of time, and is a branch of the atmospheric sciences
Atmospheric sciences
Atmospheric sciences is an umbrella term for the study of the atmosphere, its processes, the effects other systems have on the atmosphere, and the effects of the atmosphere on these other systems. Meteorology includes atmospheric chemistry and atmospheric physics with a major focus on weather...

. Basic knowledge of climate can be used within shorter term weather forecasting
Weather forecasting
Weather forecasting is the application of science and technology to predict the state of the atmosphere for a given location. Human beings have attempted to predict the weather informally for millennia, and formally since the nineteenth century...

 using analog techniques such as the El Niño – Southern Oscillation (ENSO
Ensō is a Japanese word meaning "circle" and a concept strongly associated with Zen. Ensō is one of the most common subjects of Japanese calligraphy even though it is a symbol and not a character. It symbolizes the Absolute enlightenment, strength, elegance, the Universe, and the void; it can...

), the Madden-Julian Oscillation (MJO), the North Atlantic Oscillation (NAO
NAO can refer to:* National Applications Office, an agent of the United States Department of Homeland Security* National Audit Office in several nations* Nautical Almanac Office in several nations...

), the Northern Annualar Mode (NAM), the Arctic oscillation
Arctic oscillation
The Arctic oscillation or Northern Annular Mode/Northern Hemisphere Annular Mode is an index of the dominant pattern of non-seasonal sea-level pressure variations north of 20N latitude, and it is characterized by pressure anomalies of one sign in the Arctic with the opposite anomalies centered...

 (AO), the Northern Pacific (NP) Index, the Pacific Decadal Oscillation
Pacific decadal oscillation
The Pacific Decadal Oscillation is a pattern of Pacific climate variability that shifts phases on at least inter-decadal time scale, usually about 20 to 30 years. The PDO is detected as warm or cool surface waters in the Pacific Ocean, north of 20° N...

 (PDO), and the Interdecadal Pacific Oscillation (IPO).