Daily Report

(last updated 19 Mar 2019 23:30 UT)

SUBJ: SWS DAILY SOLAR AND GEOPHYSICAL REPORT ISSUED AT 2330UT/19 MARCH 2019 BY Space Weather Services FROM THE AUSTRALIAN SPACE FORECAST CENTRE SUMMARY FOR 19 MARCH AND FORECAST FOR 20 MARCH - 22 MARCH STATUS INDICATORS SOL:GREEN MAG:GREEN ION: GREEN ----------------------------------------------------------- 1A. SOLAR SUMMARY Activity 19 Mar: Very low Flares: none. Observed 10.7 cm flux/Equivalent Sunspot Number for 19 Mar: 70/5 1B. SOLAR FORECAST 20 Mar 21 Mar 22 Mar 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 was Very Low for the UT day 19 March. Currently there is one spotted region on the visible disc, AR2735. Solar activity is expected to remain Very Low for the next 3 UT days, 20-22 March, with a slight chance for C-class flares. No Earth directed CMEs were observed in the available imagery. The solar wind speed was near its background levels up to 19/1330 UT, then it increased to 410 km/s. At the time of this report the solar wind speed is near 400 km/s. The total IMF (Bt) ranged between 1 nT and 3 nT up to 19/0820 UT, then it abruptly increased to 7 nT and then varied in the range 4-7 nT. After 0820 UT the north-south component of IMF (Bz) was oscillating between +7 nT and -6 nT. Solar wind speed is expected to remain moderately enhanced during the next UT day, 20 March, due to the high-speed solar wind stream from the recurrent equatorial coronal hole. ----------------------------------------------------------- 2A. MAGNETIC SUMMARY Geomagnetic field for Australian Region 19 Mar: Quiet Estimated Indices 19 Mar : A K Australian Region 5 11122122 Cocos Island 5 11122122 Darwin 4 12122111 Townsville 5 11222221 Learmonth 6 11222222 Alice Springs 5 11122122 Culgoora 4 11122121 Gingin 5 11112123 Canberra 4 01112122 Launceston 5 11222122 Hobart 4 11112122 Estimated Antarctic Regional K Indices 19 Mar : Macquarie Island 3 10122110 Casey 10 24322122 Mawson 29 23222275 Davis 10 13322233 Observed Regional daily pc3 Indices 19 Mar : Darwin 0 (Quiet) Townsville NA 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 19 Mar : A Fredericksburg 6 Planetary 7 Observed AFr/Ap Indices 18 Mar : A K Fredericksburg 2 Planetary 2 0100 1001 2B. MAGNETIC FORECAST Date Ap Conditions 20 Mar 8 Quiet to Unsettled 21 Mar 6 Quiet 22 Mar 6 Quiet COMMENT: Quiet conditions were observed across the Australian region on 19 March and mostly Quiet to Unsettled conditions were in Antarctica. For 20 March, the global geomagnetic activity is expected to be at Quiet to Unsettled levels with possible isolated Active periods. The predicted increase in the geomagnetic activity is due to the high speed solar wind stream from the recurrent equatorial coronal hole. Then the global geomagnetic activity is expected to return to mostly Quiet levels as the coronal hole effects wane. ----------------------------------------------------------- 3A. GLOBAL HF PROPAGATION SUMMARY Latitude Band Date Low Middle High 19 Mar Normal Normal Normal-fair PCA Event : No event. 3B. GLOBAL HF PROPAGATION FORECAST Latitude Band Date Low Middle High 20 Mar Normal Normal Normal-fair 21 Mar Normal Normal Normal-fair 22 Mar Normal Normal Normal-fair COMMENT: Mostly normal HF conditions were observed on 19 March. Occasional moderate depressions were observed at low latitudes. Similar HF conditions are expected for the next 3 UT days, 20-22 March, with a chance of moderately depressed MUFs mostly at high latitudes as a consequence of the predicted increase in the geomagnetic activity for 20 March. ----------------------------------------------------------- 4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY Date T index 19 Mar -6 Observed Australian Regional MUFs Cocos Island Region: Near predicted monthly values during local day. Enhanced by 55% during local night. Niue Island Region: Enhanced by 15% during local day. Near predicted monthly values during local night. Northern Australian Region: Depressed by 20% during local day. Near predicted monthly values during local night. Southern Australian Region: Mostly near predicted monthly values. Antarctic Region (Casey/Scott Base/Davis/Mawson): Near predicted monthly values over the UT day. Monthly T index: Month T index Feb -15 Mar -12 Apr -13 4B. AUSTRALIAN REGION IONOSPHERIC FORECAST Date T index MUFs 20 Mar -5 Near predicted monthly values 21 Mar -5 Near predicted monthly values/depressed 5 to 20% 22 Mar -5 Near predicted monthly values/depressed 5 to 20% COMMENT: Mostly near predicted monthly MUFs were observed for Australian region on UT day 19 March, with mild depressions for Northern Australian region during local day. Similar conditions are expected for the next 3 UT days, 20-22 March, with a chance of further MUF depressions for Northern and Southern Australian regions. ----------------------------------------------------------- 5. SPACE ENVIRONMENT SUMMARY GOES satellite data for 18 Mar Daily Proton Fluence >1 MeV: 4.1E+05 Daily Proton Fluence >10 MeV: 1.7E+04 Daily Electron Fluence >2 MeV: 2.70E+07 (normal fluence) Electron Fluence Daily Deep Dielectric Discharge Probability: 4% Fluence (flux accumulation over 24hrs)/ cm2-ster-day. X-ray background: <A1.0 DSCOVR Satellite Solar Wind Day Averaged Data for 18 Mar Speed: 341 km/sec Density: 5.5 p/cc Temp: 32300 K Bz: 1 nT (Courtesy Space Weather Prediction Center, Boulder USA) -----------------------------------------------------------