Daily Report

(last updated 14 Dec 2018 23:34 UT)

SUBJ: SWS DAILY SOLAR AND GEOPHYSICAL REPORT ISSUED AT 2330UT/14 DECEMBER 2018 BY Space Weather Services FROM THE AUSTRALIAN SPACE FORECAST CENTRE SUMMARY FOR 14 DECEMBER AND FORECAST FOR 15 DECEMBER - 17 DECEMBER STATUS INDICATORS SOL:GREEN MAG:GREEN ION: ** YELLOW ** ----------------------------------------------------------- 1A. SOLAR SUMMARY Activity 14 Dec: Very low Flares: none. Observed 10.7 cm flux/Equivalent Sunspot Number for 14 Dec: 71/6 1B. SOLAR FORECAST 15 Dec 16 Dec 17 Dec Activity Very low Very low Very low Fadeouts None expected None expected None expected 10.7cm/SSN 70/5 70/5 70/5 COMMENT: Solar activity remained Very Low on UT day 14 December. There is currently one numbered sunspot region on the visible solar disc. Solar activity is expected to stay Very Low for the next three UT days, 15-17 December. No Earth directed CMEs were observed in the available coronagraph imagery. On UT day 14 December, the solar wind speed varied between 340 km/s and 400 km/s, currently around 350 km/s. During the last 24 hours, the total IMF (Bt) fluctuated between 2 to 6 nT and the north-south component of IMF (Bz) fluctuated between +/-4 nT. The solar winds may become enhanced late on UT day 15 December or on UT day 16 due to the effects of a recurrent negative polarity southern hemisphere coronal hole. ----------------------------------------------------------- 2A. MAGNETIC SUMMARY Geomagnetic field for Australian Region 14 Dec: Quiet Estimated Indices 14 Dec : A K Australian Region 2 21110101 Cocos Island 1 11000100 Darwin 2 20100101 Townsville 2 21100101 Learmonth 2 21010101 Alice Springs 1 11000101 Culgoora 2 21100101 Gingin 2 21010101 Canberra 2 21110101 Launceston 3 22110111 Hobart 2 21110001 Estimated Antarctic Regional K Indices 14 Dec : Macquarie Island 1 21000000 Casey 12 44321122 Mawson 9 33221123 Davis 10 33332112 Observed Regional daily pc3 Indices 14 Dec : Darwin 0 (Quiet) Townsville 0 (Quiet) Learmonth 0 (Quiet) Alice Springs 0 (Quiet) Gingin 0 (Quiet) Canberra 0 (Quiet) Melbourne NA Pc3 pulsations are high frequency (10-45 second period) variations of the Earths magnetic field. Daily pc3-indices are the daily sum of 20 minute pc3-indices for that station and have been shown to be well correlated with rejection of high resolution aeromagnetic survey flight-line data. NOTE: Indices may have been generated from data obtained in cooperation with the following organisations: Geoscience Australia, University of Newcastle Space Physics Group, Australian Government Antarctic Division and International Center for Space Weather Science and Education, Japan. Estimated AFr/Ap Indices 14 Dec : A Fredericksburg 3 Planetary 3 Observed AFr/Ap Indices 13 Dec : A K Fredericksburg 2 Planetary 2 0100 0100 2B. MAGNETIC FORECAST Date Ap Conditions 15 Dec 8 Quiet, with possible Unsettled to Active levels late in the day 16 Dec 10 Unsettled to Active 17 Dec 8 Unsettled to Active COMMENT: Quiet geomagnetic conditions were observed in the Australian region on UT day 14 December. Mainly Quiet to Unsettled levels were observed in Antarctica, with an isolated Active period. During the next UT day, 15 December, the global geomagnetic activity is expected to be mainly Quiet. Geomagnetic activity may increase to Unsettled to Active levels late on UT day 15 December or on UT day 16 December if the solar wind becomes enhanced due to the influence of a recurrent coronal hole. ----------------------------------------------------------- 3A. GLOBAL HF PROPAGATION SUMMARY Latitude Band Date Low Middle High 14 Dec Normal Normal Normal-fair PCA Event : No event. 3B. GLOBAL HF PROPAGATION FORECAST Latitude Band Date Low Middle High 15 Dec Normal Normal Normal-fair 16 Dec Normal Normal Normal-fair 17 Dec Normal Normal Normal-fair COMMENT: On UT day 14 December, there were significant MUF depressions over the Southern Hemisphere as compared to the monthly predicted levels due to very low levels of ionising radiation from the Sun. Similar depressions are possible on UT day 15 December as the solar effects persist. ----------------------------------------------------------- 4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY Date T index 14 Dec -50 Observed Australian Regional MUFs Cocos Island Region: No data available during local day. No data available during local night. Niue Island Region: Near predicted monthly values during local day. Depressed by 40% during local night. Depressed by 25% after local dawn. Northern Australian Region: Near predicted monthly values during local day. Depressed by 35% during local night. Southern Australian Region: Near predicted monthly values during local day. Depressed by 25% during local night. Antarctic Region (Casey/Scott Base/Davis/Mawson): Near predicted monthly values over the UT day. Monthly T index: Month T index Nov -32 Dec -8 Jan -9 4B. AUSTRALIAN REGION IONOSPHERIC FORECAST Date T index MUFs 15 Dec -40 Depressed 15 to 35%/near predicted monthly values 16 Dec -30 Depressed 15 to 30%/near predicted monthly values 17 Dec -30 Depressed 15 to 30%/near predicted monthly values COMMENT: SWS HF Communications Warning 26 was issued on 13 December and is current for 14-15 Dec. On UT day 14 December, there were minor to moderate MUF depressions across the Australian region as compared to the monthly predicted levels, with some severe MUF depressions during the local night in the Niue Island, Northern Australian, and Central Australian regions. Sporadic E layers were seen across the Australian region and in Antarctica. Similar conditions are expected for UT day, 15 December, as a consequence of the continued very low levels of ionising radiation from the Sun. Depressions may lessen on UT day, 16 December, in response to possible geomagnetic activity due to an approaching coronal hole. ----------------------------------------------------------- 5. SPACE ENVIRONMENT SUMMARY GOES satellite data for 13 Dec Daily Proton Fluence >1 MeV: 2.4E+06 Daily Proton Fluence >10 MeV: 1.6E+04 Daily Electron Fluence >2 MeV: 1.00E+08 (normal fluence) Electron Fluence Daily Deep Dielectric Discharge Probability:10% Fluence (flux accumulation over 24hrs)/ cm2-ster-day. X-ray background: A1.0 DSCOVR Satellite Solar Wind Day Averaged Data for 13 Dec Speed: 400 km/sec Density: 3.2 p/cc Temp: 34000 K Bz: 0 nT (Courtesy Space Weather Prediction Center, Boulder USA) -----------------------------------------------------------