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- Polar_mesospheric_summer_echoes abstract "Polar mesospheric summer echoes (PMSE) is the phenomenon of anomalous radar echoes found between 80-90 km in altitude from May through early August in the Arctic, and from November through to February in the Antarctic. These strong radar echoes are associated with the extremely cold temperatures that occur above continental Antarctica during the summer. Rocket and radar measurements indicate that a partial reflection from a multitude of ion layers and constructive interference causes at least some of the PMSE.Generally PMSE exhibits dramatic variations in height and intensity as well as large variations in Doppler shift. PMSE exhibit strong signal power enhancements of scattering cross section at VHF radar frequencies in the range 50 MHz to 250 MHz, at times even to over 1 GHz, that occur in summer at high latitudes. The peak PMSE height is slightly below the summer mesopause temperature minimum at 88 km, and above the noctilucent cloud (NLC) and/or polar mesospheric cloud (PMC) layer at 83–84 km. The usual instrument for observing PMSE is the a VHF Mesosphere-Stratosphere-Troposphere (MST) radar, although lidars and sounding rockets have also been used. PMSE is believed to be caused by structural irregularities in the ionospheric electron density at lower altitudes. The exact cause of PMSE is not yet known, although theorists have proposed steep electron density gradients, heavy positive ions, dressed aerosols, gravity waves and turbulence as possible explanations.PMSE occurs in both the Arctic and Antarctic regions, and is sometimes accompanied by noctilucent clouds.".
- Polar_mesospheric_summer_echoes wikiPageExternalLink default.asp?casid=14831.
- Polar_mesospheric_summer_echoes wikiPageExternalLink acp-4-2601-2004.html.
- Polar_mesospheric_summer_echoes wikiPageExternalLink pmse.html.
- Polar_mesospheric_summer_echoes wikiPageID "2098714".
- Polar_mesospheric_summer_echoes wikiPageLength "2118".
- Polar_mesospheric_summer_echoes wikiPageOutDegree "11".
- Polar_mesospheric_summer_echoes wikiPageRevisionID "457152096".
- Polar_mesospheric_summer_echoes wikiPageWikiLink Category:Radio_frequency_propagation.
- Polar_mesospheric_summer_echoes wikiPageWikiLink Density_gradient.
- Polar_mesospheric_summer_echoes wikiPageWikiLink Electron.
- Polar_mesospheric_summer_echoes wikiPageWikiLink Ionosphere.
- Polar_mesospheric_summer_echoes wikiPageWikiLink Lidar.
- Polar_mesospheric_summer_echoes wikiPageWikiLink Mesosphere.
- Polar_mesospheric_summer_echoes wikiPageWikiLink Noctilucent_cloud.
- Polar_mesospheric_summer_echoes wikiPageWikiLink Radar.
- Polar_mesospheric_summer_echoes wikiPageWikiLink Stratosphere.
- Polar_mesospheric_summer_echoes wikiPageWikiLink Troposphere.
- Polar_mesospheric_summer_echoes wikiPageWikiLink Very_high_frequency.
- Polar_mesospheric_summer_echoes wikiPageWikiLinkText "PMSE".
- Polar_mesospheric_summer_echoes wikiPageWikiLinkText "Polar mesospheric summer echoes".
- Polar_mesospheric_summer_echoes wikiPageWikiLinkText "polar mesospheric summer echoes".
- Polar_mesospheric_summer_echoes wikiPageUsesTemplate Template:Science-stub.
- Polar_mesospheric_summer_echoes subject Category:Radio_frequency_propagation.
- Polar_mesospheric_summer_echoes hypernym Phenomenon.
- Polar_mesospheric_summer_echoes type Disease.
- Polar_mesospheric_summer_echoes type Redirect.
- Polar_mesospheric_summer_echoes comment "Polar mesospheric summer echoes (PMSE) is the phenomenon of anomalous radar echoes found between 80-90 km in altitude from May through early August in the Arctic, and from November through to February in the Antarctic. These strong radar echoes are associated with the extremely cold temperatures that occur above continental Antarctica during the summer.".
- Polar_mesospheric_summer_echoes label "Polar mesospheric summer echoes".
- Polar_mesospheric_summer_echoes sameAs Q7209089.
- Polar_mesospheric_summer_echoes sameAs m.06m04b.
- Polar_mesospheric_summer_echoes sameAs Q7209089.
- Polar_mesospheric_summer_echoes wasDerivedFrom Polar_mesospheric_summer_echoes?oldid=457152096.
- Polar_mesospheric_summer_echoes isPrimaryTopicOf Polar_mesospheric_summer_echoes.