Richard Lindsay Dowden

MSc PhD DSc Tas FRSNZ

Richard Dowden FRSNZ

Richard ("Dick") Dowden died in Dunedin, New Zealand on 15 December 2016, after a short illness.

Dick originally graduated from the University of Sydney School of Physics and spent a few months with the Radiophysics Division of CSIRO, then on the Sydney campus. He worked for a year in the sub-Antarctic on Macquarie Island in 1955-56, just before the International Geophysics Year, and then started graduate research while employed in Tasmania. In those eight years he acquired an MSc, PhD, and later a DSc. From 1957 to 1963 he served as a physicist in the Ionospheric Prediction Service based in Hobart, before working at the University of Tasmania as lecturer and senior lecturer from 1963 to 1966. In 1966 he was appointed Professor at the University of Otago in New Zealand, retiring to become an Emeritus Professor in 1998.

Through his long career he worked on multiple different scientific topics spanning all the electromagnetic frequency range from ULF to HF. Dick made a number of fundamental contributions in several fields of planetary and geophysics, mostly using electromagnetic theory and techniques. He was involved in fundamental theory, the understanding and interpretation of electromagnetic signals, and the design and construction of hardware.

One of his earliest significant discoveries was the deduction of the polarity and longitude of the dipole axis of the magnetic field of Jupiter from 10 MHz radio bursts. This was in 1963, more than a 10 years before Pioneer 10 arrived at Jupiter, and relied upon state of the art ground-based observations and detailed radio science knowledge. We believe that Dick was the first to interpret the radio emissions from Jupiter in a way to deduce physical parameters.

Another ground-breaking example was the first correct theory put forward to explain the generation of VLF emissions ("whistler mode chorus") generated by radiation belt electrons through anomalous Doppler shifted resonance. He also provided an explanation of the dynamic spectral (frequency-time plane) shape of "hooks", "risers", etc, in terms of a phase bunch of electrons travelling along a geomagnetic field line. He verified that short-range echoes observed on HF ionospheric sounders located near the sea were caused by coherent backscatter from sea waves which led him to suggest sea scatter radar as an oceanographical tool. He undertook the first recordings of whistler mode signals remote from the conjugate of a VLF transmitter, reception on the ground of non-ducted whistlers, VLF generation by modulation of the auroral electrojet by an ionospheric heater, identification of phase perturbations ("phase Trimpis") in association with whistlers, identification and interpretation of VLF perturbations caused by red sprites, and the first ground observation and video capture of red sprites outside the USA.

National research funding bodies are recent developments in New Zealand and Australia. Thus, in addition to being an experimentalist and theoretician, Dowden had to design and (usually) make his research equipment himself. For VLF dynamic spectra he devised the "Dynagraph" that used a tape recorder with a device to give repeated (about 500 times) sampling of every portion of tape. Other inventions were the Jupiter polarimeter which suppressed man-made transmissions near 10 MHz and the RF heating beam scanning system used at the Max-Planck-Institut fur Aeronomie's Ionospheric Heating facility at Tromsø in Norway (though designed and built in Dunedin, New Zealand). From the late 1990s the "OMSK" and later the "OmniPAL" VLF receivers used for Trimpi studies were also designed and built by Dowden and his students.

Professor Dowden was an active member of the international scientific community, a member of the American Geophysical Union since 1966, a Fellow of the Institute of Physics (UK) from 1968, Fellow of the Royal Society of New Zealand since 1983, and Fellow of the American Geophysical Union from 2003. He served as Vice President of the International Union of Radio Science (URSI) from 1987-1993. In addition, Dick was the Beverly Professor of Physics and Michaelis Medal recipient of the University of Otago, a former President of the New Zealand Institute of Physics, Commission Chairman and Editor-in-Chief of the URSI Radioscientist, Member of the International Astronautical Academy, T. K. Sidey Medal recipient of the Royal Society of New Zealand, Australian Antarctic Division Medal recipient, Member Otago Polytechnic Council, Member Otago Museum Trust Board, and Founding Director of Low Frequency Electromagnetic Research Ltd.

Richard Dowden was one of the foremost geophysicists in the Oceania region. As such he was strongly involved in the organisation of international meetings held inside this region, and served as the regional editor of the Journal of Atmospheric and Solar Terrestrial Physics (1990-1998). After retiring from the University of Otago in New Zealand in 1998, he remained scientifically active for more than a decade. In that period he developed the idea behind the "TOGA technique", which is at the heart of the global real-time World Wide Lightning Location Network (WWLLN).

As an academic for many years Dick was an active teacher, lecturing students in all levels of undergraduate and graduate courses. He also supervised many postgraduate students, including both of the authors of this memoriam, who remember his innovative ideas, his boundless enthusiasm and his inspiring encouragement. Since his death the Otago University Physics Department has been contacted by former students who remember him as a very enthusiastic lecturer.

His funeral was held in Dunedin on Saturday 17 December 2016. Later that day a memorial service occurred at the Staff Club of the University of Otago. Dick is survived by his wife Eleanor, their eight children and 11 grandchildren.

Craig J. Rodger

Professor and Head of the Physics Department, University of Otago

Neil R. Thomson

Associate Professor of Physics, University of Otago, President of the NZ URSI Member Committee

Bibliography

1. Dowden, R.L., Short-range echoes observed on ionospheric recorders, J. Atmospheric and Terrestrial Physics, 11:111-117 (1957).
2. Dowden, R.L., Ionospheric thermal radiation at radio-frequencies in the auroral zone, J. Atmospheric and Terrestrial Physics, 18:8-19 (1960).
3. Dowden, R.L. and G.T.Goldstone, 'Whistler-mode' echoes remote from the conjugate point, Nature, 183:385-386 (1959).
4. Dowden, R.L., L.F. Radio noise from the aurora, Nature,  184:803 (1959).
5. Dowden, R.L., Geomagnetic noise at 230 kc/s, Nature, 187:677-678 (1960).
6. Dowden, R.L., A theoretical model of electron density along a geomagnetic line of force in the exosphere, J. Atmospheric and Terrestrial Physics, 20:122-130 (1961).
7. Dowden, R.L., Simultaneous observations of VLF noise ('hiss') at Hobart and Macquarie Island, J. Geophysical Research, 66:1587-1588 (1961).
8. Dowden, R.L., Wide band bursts of VLF radio noise ('hiss') at Hobart, Australian J. Physics, 15:114-119 (1962).
9. Dowden, R.L., Doppler shifted cyclotron radiation from electrons:  A theory of VLF emissions, J. Geophysical Research, 67:1745-1750 (1962).
10. Dowden, R.L., Theory of generation of exospheric VLF noise ('hiss'), J. Geophysical Research, 67:2223-2230 (1962).
11. Dowden, R.L., 'Scale frequency' of the exosphere, Nature, 195:984-985 (1962).
12. Dowden, R.L., Cyclotron theory of VLF discrete emissions, Nature,  195:1085-1086 (1962).
13. Dowden, R.L., Very-low-frequency discrete emissions received at conjugate points, Nature, 195:64 (1962).
14. Dowden, R.L., Authors reply to the preceding discussion (of paper 9), J. Geophysical Research, 67:4900-4902 (1962).
15. Dowden, R.L., Method of measurement of electron energies and other data from spectrograms of VLF emissions, Australian J. Physics, 15:490-503 (1962).
16. Dowden, R.L., Doppler shifted  cyclotron generation of exospheric VLF noise ('hiss'), Planetary and Space Science, 11:361-369 (1963).
17. Dowden, R.L., Effect of Magnetic Anomalies on VLF discrete emissions, Australian J. Physics, 16:588-592 (1963).
18. Dowden, R.L., A minimum reading phase sensitive detector, Proceedings of the Institute of Radio Engineers, 51:231 (1963).
19. Dowden, R.L., Polarization measurements of Jupiter radio bursts, Australian J. Physics, 16:398-410 (1963).
20. Dowden, R.L., A Jupiter model of pulsars, Proceedings of the Astrononmical Society of Australasia, 1:4, 159 (1968).
21. Dowden, R.L., 'Micropulsation mode' propagation in the magnetosphere, Planetary and Space Science,13:761-772 (1965).
22. Dowden, R.L. and Emery, M.W., The use of micropulsation 'whistlers' in the study of the outer magnetosphere, Planetary and Space Science,13:773-779 (1965).
23. Dowden, R.L. and Emery, M.W.,  An automatic dynamic spectrum analyser for tape recorded signals, Nature, 207:493-495 (1965).
24. Dowden, R.L., Ordinary mode whistlers observed in satellites, Nature,  207:963-964 (1965).
25. Dowden, R.L., Micropulsation 'nose whistlers'.   A helium explanation, Planetary and Space Science,14:1273-1280 (1966).
26. Dowden, R.L., Possible helium ion effects in micropulsation spectrograms, J. Geophysical Research, 72:2029-2031 (1967).
27. Dowden, R.L., Dotted pearl micropulsations, J. Geophysical Research, 73:2995-3003 (1968).
28. Dowden, R.L., Location of generation regions (in L and ) of mid-latitude VLF discrete emmissions by dispersion analysis of ground station observations, J. Geophysical Research, 76:1729-1737 (1971).
29. Dowden, R.L., Electron energy spectrum and structure deduced from analysis of VLF discrete emissions by using the Helliwell criterion, J. Geophysical Research, 76:3034-3045 (1971).
30. Dowden, R.L., VLF discrete emissions deduced from Helliwell's theory, J. Geophysical Research, 76:3046-3054 (1971).
31. Dowden, R.L., Distinctions between mid-latitude VLF hiss and discrete emissions, Planetary and Space Science,19:374-376 (1971).
32. Dowden, R.L. and Allcock, G.McK, Determination of nose frequency and non-nose whistlers, J. Atmospheric and Terrestrial Physics, 33:1125-1129 (1971).
33. Dowden, R.L., Trigger delay in whistler precursors, J. Geophysical Research, 77:695-699 (1972).
34. Offen, R.J. and Dowden, R.L., Diurnal effects in Pc1 hydromagnetic whistlers:  an early afternoon source model, Planetary and Space Science,20:1661-1670 (1972).
35. Dowden, R.L., Use of electron and proton beams for production of VLF and HM emissions, J. Geophysical Research, 78:684-696 (1973).
36. McPherson, D.A., Koons, H.C., Dazey, M.H., Dowden, R.L., Amon, L.E.S, and Thomson, N.R., Alaska to New Zealand whistler mode transmissions at 6.8 kHz, Nature,  248:493 (1974).
37. McPherson, D.A., Koons, H.C., Dazey, M.H., Dowden, R.L., Amon, L.E.S, and Thomson, N.R., Conjugate magnetospheric transmissions at VLF from Alaska to New Zealand, J. Geophysical Research, 79:1555 (1974).
38. Koons, H.C., Edgar, B.C., Dowden, R.L., Carrington, C.G.and Amon, L.E.S., Multipath doppler shifts in man-made VLF signals, in ELF-VLF Radio Wave Propagation, edited by Jan Holtet, D.Reidel Publishing Co., Dordrecht-Holland (1974).
39. Groth,M.J. and Dowden, R.L., Spectra of the high frequency millisecond radio emissions from Jupiter, Nature,  255:382-384 (1975).
40. Koons, H.C., Dowden, R.L., and Amon, L.E.S., A controlled VLF phase reversal experiment in the magnetosphere, J. Geophysical Research, 81:5536-5540 (1976).
41. Dowden, R.L. and Rycroft, M.J., Wave injection experiments and wave-particle interactions, In:  Space Research XVI,  Akademic Verlag Berlin, 613-629 (1976).
42. Thomson, R.J. and Dowden, R.L., Simultaneous ground and satellite reception of whistlers. 1.  Ducted whistlers, J. Atmospheric and Terrestrial Physics, 39:869-877 (1977).
43. Thomson, R.J. and Dowden, R.L., Simultaneous ground and satellite reception of whistlers.  2.  P1 whistlers, J. Atmospheric and Terrestrial Physics,  39:879-890 (1977).
44. Dowden, R.L., McKay, A.D., Amon, L.E.S., Koons, H.C.and Dazey, M.H., Linear and non-linear amplification in the magnetosphere during a 6.6 kHz transmission, J. Geophysical Research, 83:169-181 (1978).
45. Thomson, R.J. and Dowden, R.L., Ionospheric whistler propagation, J. Atmospheric and Terrestrial Physics, 40:215-221 (1978).
46. Rietveld, M.T., Dowden, R.L. and Amon, L.E.S., Micropulsations observed by whistler-mode transmissions, Nature, 276:165-167 (1978).
47. Dowden, R.L., The effect of MHD waves on the threshold wave field for initiating VLF non-linear growth and emissions, J. Geophysical Research, 86:4815-4819 (1981).
48. Dowden, R.L., P.Stubbe and H.Kopka, VLF wave generation by modulated RF heating of the electrojet ionosphere, Advances in Space Research, 1:221-223 (1981).
49. Dowden, R.L., Non-linear magnetospheric amplification of VLF transmissions, Advances in Space Research, 1:173-182 (1981).
50. P.Stubbe, H.Kopka, A.Brekke, T.Hansen, O.Holt, Dowden, R.L., T.B.Jones, T.Robinson, H.-J.Lotz and J.Watermann, , First results from the Tromso Ionospheric Modulation Facility.  Presented  at the AGARD Symposium on The physical basis of the ionosphere in the solar-terrestrial system, Conference Proceedings, 16:1-16:9, No. 295 (1980).
51. P. Stubbe, H. Kopka,and Dowden, R.L., Generation of ELF and VLF waves by polar electrojet modulation:  experimental results, J. Geophysical Research, 86:9073:9078 (1981).
52. Dowden, R.L. and N.G.Kleimenova, 4.5 kHz ground hiss and field aligned current in the dayside cusp, J. Geophysical Research, 86:10127-10128 (1981).
53. Dowden, R.L., VLF radio noise from solar electrons at Vanda, N. Z. Antarctic Record,  3:12-15 (1981).
54. P.Stubbe, H.Kopka, M.T.Rietveld, and Dowden, R.L., Generation of ELF and VLF waves by modulated HF heating of the polar electrojet. Presented at the AGARD Symposium on Medium, Long and Very Long Wave Propagation, Conference Proceedings, 9:1-9:6, September (1981).
55. Dowden, R.L., Active experiments in space plasmas, Papers from Open Symposium (OS2) on Active Experiments in Space Plasmas during the XXI General Assembly of the International Union of Radio Science (URSI) Florence, Italy, August 1984, J. Atmospheric and Terrestrial Physics, 47 (Principal Guest Editor) (1985).
56. Dowden, R.L., Generation of VLF and ELF waves for active probing,.J. Geomagnetism and Geoelectricity , 40:1131-1140 (1988).
57. Dowden, R.L., and R.H.Holzworth, Sub-ionospheric propagation at 5 kHz over and in the vicinity of Antarctica,.J. Geomagnetism and Geoelectricity, 40:1437, (1988).
58. Dowden, R.L., and Adams, C.D.D., Phase and amplitude perturbations on subionospheric signals explained in terms of echoes from lightning-induced electron precipitation ionization patches, J. Geophysical Research, 93:11,543 (1988).
59. Dowden, R.L., and Adams, C.D.D., Phase and amplitude perturbations on the NWC signal at Dunedin from lightning-induced electron precipitation, J. Geophysical Research, 94:497-503 (1989).
60. Dowden, R.L., and Adams, C.D.D., Modal Effects on amplitude perturbations on subionospheric signals (Trimpis) deduced from two-frequency measurements, J. Geophysical Research, 94:1515-1519 (1989).
61. Adams, C.D.D. and Dowden, R.L., VLF group delay of LEP echoes from measurement of phase and amplitude perturbations at two frequencies, J. Geophysical Research, 95:2457 (1990).
62. Dowden, R.L., and Adams, C.D.D., Location of LEP from measurement of phase and amplitude perturbations on spaced antennas and on two frequencies, J. Geophysical Research, 95:4135-4145, 1990.
63. Dowden, R.L. and Holzworth, R.H., Longitudinal variation of midlatitude hiss from six long duration balloon flights,.J. Geophysical Research, 95:10,599-10,607 (1990).
64. Dowden, R.L. and Adams, C.D.D., Lightning-induced perturbations on VLF subionospheric transmissions, J. Atmospheric and Terrestrial Physics, 52:357-363 (1990).
65. Dowden, R.L., URSI-WIPP89, Papers from URSI conference on Wave -Induced Particle Precipitation and wave-particle interactions, Dunedin, NZ, February, 1989, J. Atmospheric and Terrestrial Physics, 52 (Guest Editor) (1990).
66. Dowden, R.L., Adams, C.D.D., Rietveld, M.T., Stubbe, P.and Kopka, H., Phase and amplitude perturbations on subionospheric signals produced by a moving patch of artificially heated ionosphere J. Geophysical Research, 96:239 (1991).
67. Dowden, R.L., and Adams, C.D.D., VLF versus MF heating of the lower ionosphere, J. Geophysical Research, 96:14,179 (1991).
68. Dowden, R.L., and Adams, C.D.D., Ionospheric heating by VLF transmitters? J. Atmospheric and Terrestrial Physics., 54:1051–1059 (1992).
69. Dowden, R.L., Adams, C.D.D. and Cotton, P.D., Use of VLF transmissions in the location and mapping of lightning-induced ionisation enhancements (LIEs), J. Atmospheric and Terrestrial Physics., 54:1355-1373 (1992).
70. Friedel, R.H. W., Hughes, A.R., Dowden, R.L., and Adams, C.D.D., First observations of Trimpi Events at Durban (L=1.69) using an OMSKI receiver, J. Geophysical Research, 98:1571-1580 (1993).
71. Holzworth, R.H., Norville, K.W., Hu, H., Dowden, R.L., Adams, C.D.D., Brundell, J., Pinto Jr., O., Pinto, I. and Gonzalez, W.D., Extended Life Balloon Borne Observatories, The Radioscientist, 4:33-37 (1993).
72. Dowden, R.L., and Adams, C.D.D., Size and location of lightning-induced ionisation enhancements from measurement of VLF phase and amplitude perturbations on multiple antennas, J. Atmospheric and Terrestrial Physics., 55:1335-1359 (1993).
73. Dowden, R.L., Adams, C.D.D., VLF Holography, The Radioscientist, 4:60-65 (1993).
74. Dowden, R.L., Adams, C.D.D., Brundell, J.and Dowden, P.E., Rapid onset, rapid decay (RORD), phase and amplitude perturbations of VLF subionospheric transmissions, J. Atmospheric and Terrestrial Physics., 56:1513-1527 (1994).
75. Rodger, C. J., N. R. Thomson, and R. L. Dowden, VLF line radiation observed by satellite, J. Geophys. Res., 100: 5681 – 5689 (1995).
76. Dowden, R.L., Distortion of Trimpi shapes by high altitude winds, J. Geophysical Research, 101:315-321 (1996).
77. Dowden, R.L., Brundell, J., Lyons, W. A. and Nelson, T., The structure of red sprites and elves determined by VLF scattering, IEEE Antennas and Propagation Magazine, 38: No.3, 7-15 (June, 1996).
78. Dowden, R.L., Brundell, J., Lyons, W. A. and Nelson, T., Detection and location of red sprites by VLF scattering of subionospheric transmissions, Geophysical Research Letters, 23:1737-1740 (1996).
79. Rodger, C. J., R. L. Dowden, and N. R. Thomson, A search for ELF/VLF activity associated with earthquakes using ISIS satellite data, J. Geophys. Res., 101: 13,369 - 13,378 (1996).
80. Dowden, R.L., Brundell, J. and Lyons, W. A., Are VLF RORDs produced by scattering off sprite plasma? J. Geophysical Research, 101:19,175-19,183 (1996).
81. Ohta, K., Kitagawa, T., Shima, N., Hayakawa, M. and Dowden, R. L., Characterristics of mid-latitude whistler ducts as deduced from ground-based measurements, Geophysical Research Letters, 23:3301-3304 (1996).
82. Dowden, R.L., Comment on “VLF signatures of ionospheric disturbances associated with sprites” by Inan et al., Geophysical Research Letters, 23:3421-3422 (1996).
83. Rodger, C. J.,  J. R. Wait, and R. L. Dowden, Electromagnetic scattering from a group of thin ionised cylinders, Radio Science, 32: 907 – 912 (1997).
84. Dowden, R.L. and Rodger, C. J., A vertical-plasma-slab model for determining the lower limit to plasma density in sprite columns from VLF scatter measurements, IEEE Antennas and Propagation Magazine, 39: 44-53 (1997).
85. Dowden, R.L., Hardman, S.F., Rodger, C.J., Brundell, J.B. Logarithmic decay and Doppler shift of plasma associated with sprites (1998) Journal of Atmospheric and Solar-Terrestrial Physics, 60 (7-9), pp. 741-753.
86. Rodger, C.J., Wait, J.R., Dowden, R.L. VLF scattering from Red Sprites - Theory (1998) Journal of Atmospheric and Solar-Terrestrial Physics, 60 (7-9), pp. 755-763.
87. Rodger, C.J., Wait, J.R., Dowden, R.L. Scattering of VLF from an experimentally described sprite (1998) Journal of Atmospheric and Solar-Terrestrial Physics, 60 (7-9), pp. 765-769.
88. Dowden, R.L., Brundell, J. B., and Rodger, C. J., Temporal evolution of very strong Trimpis observed at Darwin, Australia, Geophysical Research Letters, 24:2419-2423 (1997).
89. Dowden, R. L., and Rodger, C. J., Decay of a vertical plasma column:  A model to explain VLF sprites, Geophysical Research Letters, 24:2765-2768 (1997).
90. Hardman, S., Rodger, C. J. , Dowden, R. L., and Brundell, J. B., Measurements of the VLF Scatter Pattern of the Structured Plasma of Red Sprites, IEEE Antennas and Propagation Magazine, 40: #2, 29-38 (1998).
91. Rodger, C. J., Dowden, R. L., and Thomson, N. R., Observationsof Electromagnetic Activity Associated with Earthquakes by Low-Altitude Satellites, In M. Hayakawa (Editor)Seismo-Electromagnetics, Terra Scientific Publishing, Tokyo, 1997.
92. Ohta, K., Kitagawa, T., Hayakawa, M. and Dowden, R. L., A new type of mid-latitude multipath whistler trains including a nonducted whistler, Geophysical Research Letters, 24: 2937-2940 (1997).
93. Dowden, R. L., Hardman, S., Brundell, J. B., Bahr, J. L., Kawasaki, Z., and Nomura, K., Red Sprites observed in Australia, IEEE Antennas and Propagation Magazine, 39: 106 (December, 1997).
94. Rodger, C. J., Thomson, N. R., and Dowden, R. L. 1998, Are whistler ducts created by thunderstorm electrostatic fields? J. Geophys. Res.,103: 2163-2170, (1998).
95. Rodger, C. J.,  Thomson, N. R., and Dowden, R. L., Testing the formulation of Park and Dejnakarintra to calculate thunderstorm dc electric fields, J. Geophys. Res.,103: 2171-2178 (1998).
96. Rodger, C. J.,  J. R. Wait, and R. L. Dowden, Correction to “Electromagnetic scattering from a group of thin ionised cylinders”, Radio Science, 32: 2237, (1997).
97. Rodger, C.J., Dowden, R.L. Position determination of red sprites by scattering of VLF subionospheric transmissions (1998) Geophysical Research Letters, 25 (3), pp. 281-284.
98. Rodger, C.J., Wait, J.R., Dowden, R.L., Thomson, N.R. Radiating conducting columns inside the Earth-ionosphere waveguide: Application to red sprites (1998) Journal of Atmospheric and Solar-Terrestrial Physics, 60 (12), pp. 1193-1204.
99. Dowden, R.L., Brundell, J.B., Hayakawa, M. Remote sensing by VLF using 'absolute omnipal': 1. Investigation of short path propagation for possible earthquake precursor detection (1998) Mathematical Methods in Electromagnetic Theory, MMET, Conference Proceedings, 1, pp. 29-34.
100. Dowden, R.L., Brundell, J.B., Rodger, C.J. Remote sensing by VLF using 'absolute omnipal': 1. Investigation of the decay of sprite plasma (1998) Mathematical Methods in Electromagnetic Theory, MMET, Conference Proceedings, 1, pp. 304-306.
101. Hardman, S.F., Dowden, R.L., Brundell, J.B., Bahr, J.L., Kawasaki, Z.-I., Rodger, C.J. Sprite observations in the Northern Territory of Australia (2000) Journal of Geophysical Research Atmospheres, 105 (D4), art. no. 1999JD900325, pp. 4689-4697.
102. Bähr, J.L., Brundell, J.B., Hardman, S.F., Dowden, R.L. Multi-instrument coincident detection of sprites (2000) Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere, 25 (5-6), pp. 417-422.
103. Dowden, R., Rodger, C., Brundell, J., Clilverd, M. Decay of whistler-induced electron precipitation and cloud-ionosphere electrical discharge Trimpis: Observations and analysis (2001) Radio Science, 36 (1), pp. 151-169.
104. Dowden, R.L., Rodger, C.J., Nunn, D. Minimum sprite plasma density as determined by VLF scattering (2001) IEEE Antennas and Propagation Magazine, 43 (2), pp. 12-24.
105. Clilverd, M.A., Nunn, D., Lev-Tov, S.J., Inan, U.S., Dowden, R.L., Rodger, C.J., Smith, A.J. Determining the size of lightning-induced electron precipitation patches (2002) Journal of Geophysical Research: Space Physics, 107 (A8).
106. Rodger, C.J., Clilverd, M.A., Dowden, R.L. D region reflection height modification by whistler-induced electron precipitation (2002) Journal of Geophysical Research: Space Physics, 107 (A7).
107. Brundell, J.B., Rodger, C.J., Dowden, R.L. Validation of single-station lightning location technique (2002) Radio Science, 37 (4).
108. Dowden, R.L., Brundell, J.B., Rodger, C.J. VLF lightning location by time of group arrival (TOGA) at multiple sites (2002) Journal of Atmospheric and Solar-Terrestrial Physics, 64 (7), pp. 817-830.
109. Lay, E.H., Holzworth, R.H., Rodger, C.J., Thomas, J.N., Pinto Jr., O., Dowden, R.L. WWLL global lightning detection system: Regional validation study in Brazil (2004) Geophysical Research Letters, 31 (3).
110. Thomson, N.R., Rodger, C.J., Dowden, R.L. Ionosphere gives size of greatest solar flare (2004) Geophysical Research Letters, 31 (6).
111. Rodger, C.J., Brundell, J.B., Dowden, R.L., Thomson, N.R. Location accuracy of long distance VLF lightning location network (2004) Annales Geophysicae, 22 (3), pp. 747-758.
112. Rodger, C.J., Brundell, J.B., Dowden, R.L. Location accuracy of VLF World-Wide Lightning Location (WWLL) network: Post-algorithm upgrade (2005) Annales Geophysicae, 23 (2), pp. 277-290.
113. Holzworth, R.H., Bering III, E.A., Kokorowski, M.F., Lay, E.H., Reddell, B., Kadokura, A., Yamagishi, H., Sato, N., Ejiri, M., Hirosawa, H., Yamagami, T., Torii, S., Tohyama, F., Nakagawa, M., Okada, T., Dowden, R.L. Balloon observations of temporal variation in the global circuit compared to global lightning activity (2005) Advances in Space Research, 36 (11), pp. 2223-2228.
114. Jacobson, A.R., Holzworth, R., Harlin, J., Dowden, R., Lay, E. Performance assessment of the World Wide Lightning Location Network (WWLLN), using the Los Alamos Sferic Array (LASA) as ground truth (2006) Journal of Atmospheric and Oceanic Technology, 23 (8), pp. 1082-1092.
115. Jacobson, A.R., Holzworth, R., Harlin, J., Dowden, R., Lay, E. Global real-time lightning detection (2006) Bulletin of the American Meteorological Society, 87 (11), pp. 1488-1490.
116. Rodger, C.J., Werner, S., Brundell, J.B., Lay, E.H., Thomson, N.R., Holzworth, R.H., Dowden, R.L. Detection efficiency of the VLF World-Wide Lightning Location Network (WWLLN): Initial case study (2006) Annales Geophysicae, 24 (12), pp. 3197-3214.
117. Lay, E.H., Jacobson, A.R., Holzworth, R.H., Rodger, C.J., Dowden, R.L. Local time variation in land/ocean lightning flash density as measured by the World Wide Lightning Location Network (2007) Journal of Geophysical Research Atmospheres, 112 (13), art. no. D13111.
118. Williams, E.R., Mushtak, V.C., Boldi, R., Dowden, R.L., Kawasaki, Z.-I. Sprite lightning heard round the world by Schumann resonance methods (2007) Radio Science, 42 (2), art. no. RS2S20.
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Obituary was lodged on website on 3 April 2017.