Bulletin American Meteorological Society Miller, L. Jay, 1972: Dual-Doppler radar observations of Snider, J. B., 1972: Ground-based sensing of temperature circulation in snow conditions. Proc. 15th Radar Meteor. profiles from angular and multi-spectral emission measure- Conf., Amer. Meteor. Soc. ments. J. Appl. Meteor11, 958-967. Owens, J. C., 1969: Optical Doppler measurement of micro- scale wind velocity. Proc. IEEE, 57, 530-536. Strauch, R. G., V. E. Derr, and R. E. Cupp, 1971: Atmo- Richter, J. H., 1969: High resolution tropospheric radar spheric temperature measurement using Raman lidar. sounding. Radio Sci., 4, 1261-1268. Appl Opt., 10, 2665-1669. Salzman, J. A., W. J. Masica, and T. A. Coney, 1971: Deter- V. E. Derr, and R. E. Cupp, 1972: Atmospheric water mination of gas temperatures from laser-Raman scattering. vapor meaesurement using Raman lidar. Remote Sensing NASA TN D-6336. of Environment (in press). Schotland, R. M., 1969: Some aspects of remote atmospheric sensing by laser radar. Rept. of Remote Atrnos. Probing Wyngaard, J. E., Y. Izumi, and S. A. Collins, Jr., 1971: Be- Panel, Committee on Atrnos. Sci., Nat'l Acad, of Sci-Natl havior of the refractive-index-structure parameter near the Res. Council, 2, 179-200. ground. J. Opt. Soc. Amer., 61, 1646-1650. news and notes Lightning suppression by seeding with two chaff dispensers and field mills to measure electric field strength. Flying below cloud level, the NOAA scientists During a six-week long experiment, scientists from the waited until their instruments registered a field greater than National Oceanic and Atmospheric Administration attempted 30,000 volts per meter, a magnitude at which corona dis- to suppress lightning by seeding thunderstorms with fine charge will occur, When this happens the chaff dispensers aluminized fibers over a 200 mis area of northeastern Colo- are activated and the threadlike fibers are carried into the rado. The experiment, which was performed during the clouds by updrafts. Potential use for the technique of summer, represents the resumption of a 1965-66 lightning lightning suppression lies in the area of forest fire reduction. suppression study performed near Flagstaff, Ariz., by NOAA's Although some researchers contend that lightning and the Atmospheric Physics and Chemistry Laboratory, Boulder, fires it causes are necessary to maintain an ecological balance, Colo. the capability for suppressing lightning may nevertheless APCL's Dr. Heinz Kasemir, who again directed the light- provide foresters with the opportunity to defer forest fires ning suppression study, expected accurate results as a product from periods of extreme hazard to periods when fires can of the development of a ground network that recorded the be controlled more easily. A total suppression of lightning, strength of the field and the location of each lightning according to Alan R. Taylor of the Northern Forest Fire stroke within a 50-mi radius of the seeding. The object Laboratory, would result in 70% fewer forest fires. of the experiment was to prevent the storm's electric field from reaching lightning strength using the phenomenon of NACOA reviewing Agnes warnings corona discharge. By introducing an electrically conductive Review and evaluation of the performance of the nation's pointed object into a strong electrical field, such as is found flood forecasting and warning program during the east in a thunderstorm, scientists hoped to induce a negative and coast flood disaster of June 1972, tropical storm Agnes, is positive pole. The ions then escape on the pointed pole of being performed by the National Advisory Committee on the same charge, thereby increasing the electrical conduc- Oceans and Atmosphere (NACOA) (see BULLETIN, 52, 1127). tivity of the atmosphere; this effect is frequently visible as NOAA Administrator Dr. Robert M. White asked Dr. a faint glow, and is termed the corona effect. Scientists were William A. Nierenberg, Chairman of NACOA, to undertake hopeful that the corona effect would make the air more the review in the wake of what is being called the worst conductive, thus allowing the electric charge to continuously natural disaster in the history of the country. bleed away, obviating the strong field build-up. Preliminary estimates of the damage caused by Agnes Using this principal NOAA scientists drop chaff, alumi- were about $2 billion. Because of the extent and severity nized nylon fibers 10 cm long, in the region of the storm's of the disaster, Dr. White called for an outside evaluation electrical field, thereby increasing atmospheric conductivity, of the entire forecasting-warning-dissemination system. which in turn should neutralize the storm's electric field and NACOA will determine how the system performed and suppress lightning. how it can be improved. As thunderstorms developed or move into the test area, Kasemir and his coworkers boarded a B-26 aircraft equipped (More news and notes on page 970) 949 Unauthenticated | Downloaded 10/05/21 11:47 AM UTC Vol. 53, No. 10,, October 1972 4) How should the information contained in a credible means of describing the uncertainty inherent in fore- interval forecast be expressed when the forecast is casts of other meteorological variables. The quantitative disseminated to potential users (including the expression of this uncertainty could be of particular general public)? For example, should the median, importance in forecasts relating to severe weather phe- representing a point forecast, be included as well nomena such as hurricanes and tornadoes. as the end points of the credible interval? 10 5) What kind of program of public education should References be undertaken with regard to credible interval tem- Abrams, E., 1971: Problems in the communication of rou- tine weather information to the public. University Park, perature forecasts? In view of the fact that consid- Pennsylvania State University, Department of Meteorol- erable evidence exists that the meaning of pre- ogy, M.S. Thesis, 126 pp. cipitation probability forecasts is not clear to the Alpert, M., and H. Raiffa, 1969: A progress report on the general public (see, for example, Abrams, 1971, training of probability assessors. Cambridge, Mass., Har- and Bickert, 1967), the need for a continuing pro- vard University, unpublished manuscript, 31 pp. Bickert, C. von E., 1967: A study of the understanding and gram of public education is evident. However, the use of probability of precipitation forecasts in two major nature and content of such a program remains to cities. Denver, Colo., University of Denver, Denver Re- be determined. search Institute, Report, 106 pp. 6) What measures of "goodness" are required for Edwards, W., H. Lindman, and L. J. Savage, 1963: Bayesian statistical inference for psychological research. Psychol. credible interval temperature forecasts? Specifically, Rev., 70, 193-242. what measures are appropriate with regard to the Julian, P. R., and A. H. Murphy, 1972: Probability and sta- formulation or assessment of such forecasts in order tistics in meteorology: A review of some recent develop- to discourage hedging and what measures are suit- ments. Bull. Amer. Meteor. Soc., 53, 957-965. able for determining or evaluating the "accuracy" Murphy, A. H., 1972: Probability forecasting in meteorology: A review of recent developments. Boulder, Colo., National and "value" of such forecasts? Center for Atmospheric Research, unpublished manuscript, 20 pp. In view of the potential value of credible interval tem- , and R. L. Winkler, 1970: Scoring rules in probability perature forecasts, the experiments and studies re- assessment and evaluation. Acta Psychol, 34, 273-286. quired to answer these questions should be undertaken Peterson, C. R., and L. R. Beach, 1967: Man as an intuitive as soon as possible. statistician. Psychol. Bull., 68, 29-46. Finally, the credible interval concept also provides a Raiffa, H., 1968: Decision Analysis: Introductory Lectures on Choices under Uncertainty. Reading, Mass., Addison- io The inclusion of both the median and the end points Wesley, 332 pp. of the credible interval in the temperature forecast would Stael von Holstein, C.-A. S., 1971: The effect of learning on correspond to the present practice of including both a cate- the assessment of subjective probability distributions. gorical statement and a probability in a forecast of precipi- Org. Beh. Hum. Perf., 6, 304-315. tation occurrence. Note that the median in a temperature Winkler, R. L., 1967: The assessment of prior distributions forecast assumes particular importance when the interval is in Bayesian analysis. J. Amer. Statis. Assoc., 62, 776-800. asymmetric about the median (see the dialogue between the , and A. H. Murphy, 1968: "Good" probability assessors. experimenter and the forecaster in Section 2). /. Appl. Meteor., 7, 751-758. (Continued from news and notes, page 949) Cold water eddy no. 2 tagged was placed in the center of the eddy, the second halfway between the center and the circulation's outer edge. A cold water eddy which broke through the Gulf Stream Eddy No. 2 is the second cold water eddy to be studied by from the North Atlantic and is headed south has been tagged NOAA investigators; the first was discovered in April 1971, so that it can be identified during investigations as it moves and traced as far as 120 mi off Cape Kennedy, Fla., in southward. Scientists from the Commerce Department's Na- April 1972 before presumably being absorbed into the tional Oceanic and Atmospheric Administration aboard the northward-flowing Gulf Stream (see BULLETIN, 53, 544). Dr. NO A A Ship Mt. Mitchell dropped two identifying markers Alan E. Strong, the oceanographer in charge of the study into the eddy, which will later be searched for by other for NOAA's National Environmental Satellite Service, noted ships in an attempt to trace the route of the eddy. that the two eddies under study this year differ markedly When first located the massive body of water was moving from the feAV other Gulf Stream eddies which have been southward at a rate of about 2 mi per day.