Related by context. Frequent words. (Click for all words.) 74 sunspot activity 66 sunspot 65 sunspots 60 geomagnetic field 59 X ray emission 58 geomagnetic storm 56 cosmic ray 55 geomagnetic 55 El Ninos 54 volcanism 54 ENSO 53 occultation 53 Serreze 53 perigee 53 Little Ice Age 53 atmospheric circulation 53 glaciation 53 mid latitudes 52 gamma ray burst 52 solar flares 52 greenhouse warming 52 La Niña 52 equinox 51 oscillations 51 NSIDC 51 troposphere 51 Eta Carinae 51 aurora 51 La Nina 51 cosmic rays 50 decadal 50 quasar 50 Sunspot 50 North Atlantic Oscillation 50 meteor shower 50 Iapetus 50 infrared wavelengths 50 amplitudes 50 volcanic activity 50 equatorial Pacific 49 oscillation 49 spring equinox 49 vernal equinox 49 super Earths 49 autumnal equinox 49 atmospheric CO2 49 Perseid meteor shower 49 atmospheric carbon dioxide 49 El Niño 49 El Nino phenomenon 49 ionosphere 49 radioactive decay 49 supernova explosions 48 supernova explosion 48 cosmic microwave background 48 albedo 48 climatological 48 El Nino 48 tropical cyclones 48 greenhouse gas concentrations 48 gravitational lensing 48 HD #b [002] 48 CO2 concentrations 47 heliosphere 47 atmospheric concentrations 47 volcanic earthquakes 47 ringed planet 47 galaxy cluster 47 Saturn rings 47 radiative 47 journal Geophysical Research 47 extrasolar planet 47 Perseids 47 perturbation 47 elliptical orbit 47 GRBs 47 redshift 46 volcanic eruptions 46 dynamical 46 Grimsvotn 46 circadian clock 46 pulsar 46 ejecta 46 XMM Newton 46 CMEs 46 meteor showers 46 martian 46 Landsea 46 ozone depletion 46 seismicity 46 supernova 45 GOCE 45 Medieval Warm Period 45 magnetosphere 45 auroras 45 magnetic fields 45 precipitation 45 astronomers 45 monsoon rainfall 45 convective 45 periodicity