China sets 2060 goal to go carbon neutral

Chinese President Xi Jinping vowed Tuesday that the world's largest greenhouse gas polluter will peak emissions in 2030 and go carbon neutral by 2060, in what environmentalists hailed as a major step forward.

Unexpected wildfire emission impacts air quality worldwide

In lab studies of wildfire, nitrous acid seems like a minor actor, often underrepresented in atmospheric models. But in the real-world atmosphere, during wildfires, the chemical plays a leading role—spiking to levels significantly ...

Emissions may add 40 cm sea level rise by 2100, experts warn

Sustained greenhouse gas emissions could see global sea levels rise nearly 40 centimetres this century as ice sheets in Antarctica and Greenland continue to melt, a major international study concluded Thursday.

Siberia's permafrost erosion has been worsening for years

The Arctic is warming faster than any other region on the planet. As a result, permafrost that is thousands of years old is now being lost to erosion. As measurements gathered on the Lena River by AWI experts show, the scale ...

How Canada could benefit from a carbon budget

Canadians have understandably been preoccupied by the COVID-19 emergency. Yet the climate emergency that prompted hundreds of thousands to march in the streets in September 2019 has not subsided.

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Greenhouse

A greenhouse (also called a glasshouse) is a building in which plants are grown. These structures range in size from small sheds to very large buildings. A miniature greenhouse is known as a cold frame.

A greenhouse is a structure with different types of covering materials, such as a glass or plastic roof and frequently glass or plastic walls; it heats up because incoming visible solar radiation (for which the glass is transparent) from the sun is absorbed by plants, soil, and other things inside the building. Air warmed by the heat from hot interior surfaces is retained in the building by the roof and wall. In addition, the warmed structures and plants inside the greenhouse re-radiate some of their thermal energy in the infra-red, to which glass is partly opaque, so some of this energy is also trapped inside the glasshouse. However, this latter process is a minor player compared with the former (convective) process. Thus, the primary heating mechanism of a greenhouse is convection. This can be demonstrated by opening a small window near the roof of a greenhouse: the temperature drops considerably. This principle is the basis of the autovent automatic cooling system. Thus, the glass used for a greenhouse works as a barrier to air flow, and its effect is to trap energy within the greenhouse. The air that is warmed near the ground is prevented from rising indefinitely and flowing away.

Although there is some heat loss due to thermal conduction through the glass and other building materials, there is a net increase in energy (and therefore temperature) inside the greenhouse.

Greenhouses can be divided into glass greenhouses and plastic greenhouses. Plastics mostly used are PEfilm and multiwall sheet in PC or PMMA. Commercial glass greenhouses are often high tech production facilities for vegetables or flowers. The glass greenhouses are filled with equipment like screening installations, heating, cooling, lighting and may be automatically controlled by a computer.

This text uses material from Wikipedia, licensed under CC BY-SA