GPRS   :   

GPRS also known as: "General Packet Radio Service” is a wireless data standard used on GSM networks. It offers theoretical data rates as high as 120kbps on the downlink side, but real world speeds are typically significantly slower.

GPS   :   

The Global Positioning System is a series of satellites owned by the US government that broadcasts signals that GPS receivers on the surface of the planet can use to determine position through triangulation. The term GPS is often used to refer to a GPS receiver, such as those used in cars and sometimes found in mobile phones.

GRABEN   :   

An elongated, relatively depressed crustal unit or block that is bounded by faults on its sides.

GRANULATION   :   

A pattern of small cells seen on the surface of the Sun caused by the convective motions of the hot solar gas.

GREENHOUSE EFFECT   :   

An increase in temperature caused when the atmosphere absorbs incoming solar radiation but blocks outgoing thermal radiation; carbon dioxide is the major factor.

GREENHOUSE GASES   :   

Atmospheric gases or vapors that absorb outgoing infrared energy emitted from the Earth naturally or as a result of human activities. Greenhouse gases are components of the atmosphere that contribute to the Greenhouse effect.

GROSS PRIMARY PRODUCTIVITY (GPP)   :   

The rate at which an ecosystem accumulates biomass, including the energy it uses for the process of respiration.

GROUND TISSUE   :   

The simple non-meristematic tissues in plants that are made up of 3 cell types like parenenchyma, collenchyma and sclerenchyma are known as ground tissue. These usually form the pith, cortex or the mesophyll.

GROUNDWATER   :   

Water contained in porous strata below the surface of the Earth.

GYRE   :   

A circular or spiral motion, especially a circular ocean current.