Definitions - m

Magma

Climate change is a change in the statistical distribution of weather over periods of time that range from decades to millions of years. It can be a change in the average weather or a change in the distribution of weather events around an average (for example, greater or fewer extreme weather events). Climate change may be limited to a specific region, or may occur across the whole Earth.

In recent usage, especially in the context of environmental policy, climate change usually refers to changes in modern climate. It may be qualified as anthropogenic climate change, more generally known as global warming.

Wikipedia - Climate Change entry

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Magnetosphere

The region around the earth in which the earth's magnetic field plays a dominant part in controlling the physical processes that take place.

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Mammatus Clouds

Clouds that look like pouches hanging from the underside of a cloud.

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Mandatory Recycling

Programs which by law require consumers to separate trash so that some or all recyclable materials are recovered for recycling rather than going to landfills.

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Mantle

The part of the earth between the crust and the core.

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Mauna Loa

A volcano on the island of Hawaii where scientists have maintained the longest continuous collection of reliable daily atmospheric records.

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Mean Radiant Temperature

The average temperature experienced from the combination of all the surface temperatures in a room, i.e walls, floors, ceilings, furniture, and people.

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Mesoscale

The scale of meteorological phenomena that ranges in size from a few km to about 100 km. It includes local winds, thunderstorms, and tornadoes.

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Meteorologist

A Carbon Offset is a financial instrument representing a reduction in greenhouse gas emissions.

Wikipedia Entry

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Meteorology

The science of weather related phenomena.

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Methane

A hydrocarbon that is a greenhouse gas with a global warming potential most recently estimated at 21. Methane is produced through anaerobic (without oxygen) decomposition of waste in landfills, animal digestion, decomposition of animal wastes, production and distribution of natural gas and petroleum, coal production, and incomplete fossil fuel combustion.

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Methyl Bromide

An effective pesticide; used to fumigate soil and many agricultural products. Because it contains bromine, it depletes stratospheric ozone when released to the atmosphere.

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Metropolitan Coalescence

The merging of the urbanized areas of separate metropolitan regions; Megalopolis is an example of this process.

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Micro Inverter

This is a small Inverter that mounts on to the back of each solar panel instead of having one large Inverter used by all the panels. While it works better when partial shading is a concern, it can increase the cost of the overall system.

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Micro Wind Turbine

Micro wind turbine is an umbrella term for small scale wind turbines that are typically deployed on or near buildings and used to generate electricity that is transmitted direct to the property.

Micro wind turbines have in the past been criticized for being visually intrusive and generating less energy than expected.

However, suppliers maintain that models can generate up to 100Kw of energy and represent an efficient source of on-site renewable energy as long as they are situated correctly.

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Microburst

A strong localized downdraft less than 4 km wide that occurs beneath severe thunderstorms. A strong downdraft greater than 4 km across is called a down burst.

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Microgrid

Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds. There are three naturally occurring isotopes, with 12C and 13C being stable, while 14C is radioactive, decaying with a half-life of about 5730 years. Carbon is one of the few elements known since antiquity. The name "carbon" comes from Latin language carbo, coal.

See the full entry on wikipedia

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Midnight Zone

The area of the ocean beneath the twilight zone, extending from 3,000 feet (1,000 m) down to the ocean floor, where only about 1 percent of marine life can survive.

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Mitigation

The sale and purchase of carbon credits or pollution permits through carbon markets.

The practice is designed to help control carbon dioxide emissions by placing a price on a ton of emitted CO2 and providing members of trading schemes with economic incentives to reduce the amount of pollution they produce.

The market is dominated by cap-and-trade schemes, such as the EU's emissions trading scheme, but carbon trading can also refer to the sale of carbon offsets from emission reduction projects.

In theory, carbon trading mechanisms mean that emission reductions are achieved at the lowest possible cost, as businesses will only purchase carbon credits - effectively paying someone else to cut emissions for them - if they can not deliver emission reductions at a lower cost themselves.

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Modal

Modal is 100% biodegradable and can make a great eco alternative to viscose. It's made from beech trees in Australia and needs few fertilizers or pesticides.

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Monoculture

Crop rotation is when one grows a series of dissimilar types of crops in rotation, in the same area, in sequential seasons for various benefits such as to avoid the build up of pathogens and pests that often occurs when one species is continuously cropped. Crop rotation also seeks to balance the fertility demands of various crops to avoid excessive depletion of soil nutrients.

A traditional component of crop rotation is the replenishment of nitrogen through the use of green manure in sequence with cereals and other crops. It is one component of polyculture. Crop rotation can also improve soil structure and fertility by alternating deep-rooted and shallow-rooted plants

Crop rotation is practised by all sizes of farming, from the hobbyist to large farms.

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Mould

A coating or discoloration caused by various saprotrophic fungi that develop in a damp atmosphere on the surface of stored food, fabrics, wallpaper, etc.

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Mutagenicity

A change in the genetic material of a living organism, usually in a single gene, which can be passed on to future generations.

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