Greenhouse Effect

<p style="margin: 0.5em 0px 1em; padding: 0px; border: 0px; font-variant-numeric: inherit; font-variant-east-asian: inherit; font-stretch: inherit; line-height: inherit; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Lato, Helvetica, Arial, sans-serif; vertical-align: baseline;">The <span style="margin: 0px; padding: 0px; border: 0px; font-variant-numeric: inherit; font-variant-east-asian: inherit; font-weight: 700; font-stretch: inherit; line-height: inherit; vertical-align: baseline;">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<p style="margin: 0.5em 0px 1em; padding: 0px; border: 0px; font-variant-numeric: inherit; font-variant-east-asian: inherit; font-stretch: inherit; line-height: inherit; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Lato, Helvetica, Arial, sans-serif; vertical-align: baseline;">If a planet's atmosphere contains radiatively active gases (i.e., <a href="https://en.wikipedia.org/wiki/Greenhouse_gas" title="Greenhouse gas" style="margin: 0px; padding: 0px; border: 0px; font: inherit; vertical-align: baseline; color: rgb(107, 75, 161);">greenhouse gases</a>) they will radiate energy in all directions. Part of this radiation is directed towards the surface, warming it.<span class="mw-ref" id="cite_ref-3" style="margin: 0px; padding: 0px; border: 0px; font-variant: inherit; font-stretch: inherit; font-size: 0.75em; line-height: 1; font-family: inherit; vertical-align: super; unicode-bidi: embed;"><a href="https://en.wikipedia.org/#cite_note-3" style="margin: 0px; padding: 0px; border: 0px; font: inherit; vertical-align: baseline; color: rgb(107, 75, 161); counter-reset: mw-Ref 3;"></a> The intensity of the downward radiation – that is, the strength of the greenhouse effect – will depend on the atmosphere's temperature and on the amount of greenhouse gases that the atmosphere contains.<p style="margin: 0.5em 0px 1em; padding: 0px; border: 0px; font-variant-numeric: inherit; font-variant-east-asian: inherit; font-stretch: inherit; line-height: inherit; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Lato, Helvetica, Arial, sans-serif; vertical-align: baseline;">Earth’s natural greenhouse effect is critical to supporting life. Human activities, mainly the burning of fossil fuels and clearing of forests, have strengthened the greenhouse effect and caused <a href="https://en.wikipedia.org/wiki/Global_warming" title="Global warming" style="margin: 0px; padding: 0px; border: 0px; font: inherit; vertical-align: baseline; color: rgb(107, 75, 161);">global warming</a>.<span class="mw-ref" id="cite_ref-4" style="margin: 0px; padding: 0px; border: 0px; font-variant: inherit; font-stretch: inherit; font-size: 0.75em; line-height: 1; font-family: inherit; vertical-align: super; unicode-bidi: embed;"><a href="https://en.wikipedia.org/#cite_note-4" style="margin: 0px; padding: 0px; border: 0px; font: inherit; vertical-align: baseline; color: rgb(107, 75, 161); counter-reset: mw-Ref 4;"></a><p style="margin: 0.5em 0px 1em; padding: 0px; border: 0px; font-variant-numeric: inherit; font-variant-east-asian: inherit; font-stretch: inherit; line-height: inherit; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Lato, Helvetica, Arial, sans-serif; vertical-align: baseline;">The term "greenhouse effect" is a <a href="https://en.wikipedia.org/wiki/Misnomer" title="Misnomer" style="margin: 0px; padding: 0px; border: 0px; font: inherit; vertical-align: baseline; color: rgb(107, 75, 161);">misnomer</a>that arose from a faulty analogy with the effect of sunlight passing through glass and warming a <a href="https://en.wikipedia.org/wiki/Greenhouse" title="Greenhouse" style="margin: 0px; padding: 0px; border: 0px; font: inherit; vertical-align: baseline; color: rgb(107, 75, 161);">greenhouse</a>. The way a greenhouse retains heat is fundamentally different, as a greenhouse works mostly by reducing airflow so that warm air is kept inside,<span class="mw-ref" id="cite_ref-ipcc-AR4WG1_2-1" style="margin: 0px; padding: 0px; border: 0px; font-variant: inherit; font-stretch: inherit; font-size: 0.75em; line-height: 1; font-family: inherit; vertical-align: super; unicode-bidi: embed;"><a href="https://en.wikipedia.org/#cite_note-ipcc-AR4WG1-2" style="margin: 0px; padding: 0px; border: 0px; font: inherit; vertical-align: baseline; color: rgb(107, 75, 161); counter-reset: mw-Ref 2;"></a><span class="mw-ref" id="cite_ref-Schroeder_5-0" style="margin: 0px; padding: 0px; border: 0px; font-variant: inherit; font-stretch: inherit; font-size: 0.75em; line-height: 1; font-family: inherit; vertical-align: super; unicode-bidi: embed;"><a href="https://en.wikipedia.org/#cite_note-Schroeder-5" style="margin: 0px; padding: 0px; border: 0px; font: inherit; vertical-align: baseline; color: rgb(107, 75, 161); counter-reset: mw-Ref 5;"></a><span class="mw-ref" id="cite_ref-wood1909_6-0" style="margin: 0px; padding: 0px; border: 0px; font-variant: inherit; font-stretch: inherit; font-size: 0.75em; line-height: 1; font-family: inherit; vertical-align: super; unicode-bidi: embed;"><a href="https://en.wikipedia.org/#cite_note-wood1909-6" style="margin: 0px; padding: 0px; border: 0px; font: inherit; vertical-align: baseline; color: rgb(107, 75, 161); counter-reset: mw-Ref 6;"></a> whereas the greenhouse "effect" is the increase in temperature inside of the "house" via the re-radiation of heat energy from its gaseous "windows" which allow light energy to pass in but then trap it and reflect it when it attempts to escape as heat energy.