Climatology

Climate is the statistics of weather, usually over a 30-year interval.

El Niño /ɛl ˈniːnjoʊ/ (Spanish pronunciation: [el ˈniɲo]) is the warm phase of the El Niño Southern Oscillation (commonly called ENSO) and is associated with a band of warm ocean water that develops in the central and east-central equatorial Pacific (between approximately the International Date Line and 120°W), including off the Pacific coast of South America.

A glacial period (alternatively glacial or glaciation) is an interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances.

Phenology is the study of periodic plant and animal life cycle events and how these are influenced by seasonal and interannual variations in climate, as well as habitat factors (such as elevation).

The subtropical ridge, also known as the subtropical high or horse latitudes, is a significant belt of atmospheric high pressure situated around the latitudes of 30°N in the Northern Hemisphere and 30°S in the Southern Hemisphere.

Melt ponds are pools of open water that form on sea ice in the warmer months of spring and summer.

Acid rain is a rain or any other form of precipitation that is unusually acidic, meaning that it possesses elevated levels of hydrogen ions (low pH).

Atmospheric pressure, sometimes also called barometric pressure, is the pressure exerted by the weight of air in the atmosphere of Earth (or that of another planet).

The greenhouse effect is the process by which radiation from a planet's atmosphere warms the planet's surface to a temperature above what it would be without its atmosphere.

The term highland or uplands is used to denote any mountainous region or elevated mountainous plateau.

The Little Ice Age (LIA) was a period of cooling that occurred after the Medieval Warm Period (Medieval Climate Optimum).

Nuclear winter (also known as atomic winter) is a hypothesized global climatic effect most often considered a potential threat following a countervalue (or city-targeted), nuclear war, as a result of city and natural wildfire firestorms.

In geology, permafrost is ground, including rock or (cryotic) soil, at or below the freezing point of water 0 °C (32 °F) for two or more years.

Sea level rise has been estimated to be on average between +2.

The Westerlies, anti-trades, or Prevailing Westerlies, are prevailing winds from the west toward the east in the middle latitudes between 30 and 60 degrees latitude.

The World Day to Combat Desertification and Drought is a United Nations observance each June 17.

The Azores High (Portuguese: Anticiclone dos Açores) (also known as North Atlantic (Subtropical) High/Anticyclone or the Bermuda-Azores High, is a large subtropical semi-permanent centre of high atmospheric pressure typically found south of the Azores in the Atlantic Ocean, at the Horse latitudes. It forms one pole of the North Atlantic oscillation, the other being the Icelandic Low. The system influences the weather and climatic patterns of vast areas of North Africa and southern Europe, and to a lesser extent, eastern North America. The aridity of the Sahara Desert and the summer drought of the Mediterranean Basin is due to the large-scale subsidence and sinking motion of air in the system. In its summer position (the Bermuda High), the high is centered near Bermuda, and creates a southw

Urban climate refers to climatic conditions in an urban area that differ from neighboring rural areas, and are attributable to urban development.

Desert climate (in the Köppen climate classification BWh and BWk, sometimes also BWn), also known as an arid climate, is a climate that does not meet the criteria to be classified as a polar climate, and in which precipitation is too low to sustain any vegetation at all, or at most a very scanty shrub.

In geology and climatology, a pluvial is either a modern climate characterized by relatively high precipitation or an interval of time of variable length, decades to thousands of years, during which a climate characterized by either relatively high precipitation or humidity.

Extreme weather includes unexpectable, unusual, unpredictable severe or unseasonal weather; weather at the extremes of the historical distribution—the range that has been seen in the past.

The North Atlantic Oscillation (NAO) is a weather phenomenon in the North Atlantic Ocean of fluctuations in the difference of atmospheric pressure at sea level between the Icelandic low and the Azores high.

Outgoing Longwave Radiation (OLR) is the energy radiating from the Earth as infrared radiation at low energy to Space.

The history of the scientific discovery of climate change began in the early 19th century when ice ages and other natural changes in paleoclimate were first suspected and the natural greenhouse effect first identified.

A region is arid when it is characterized by a severe lack of available water, to the extent of hindering or preventing the growth and development of plant and animal life.

The main climate state change is between periodical glacial and interglacial cycles in Earth history, studied from climate proxies.

The ocean surface has highs and lows, similar to the hills and valleys of Earth's land surface depicted on a topographic map.