WEATHER MAN'S WORRIES

Chronicle (Levin), 11 January 1949, Page 7

WEATHER MAN'S WORRIES

Press Association)

Problems Of Giving More Accurate Forecasts

(Per

WELLINGTON, Jan. 10. "Forecasts are not a guarantee of t'uture weather but a pretty sure indication of it. " This was statecl today by the research oliieer for meteorology in New Zealand, Mr. ,T. W. Huteliings, who eulimerated some of the difiieullies met with. Seventy per tent, of forecasts at least, he said, were correct tliough the public fourid it#natural to remember the errors better. There could be no certaintv in forecasting while meteorology remained a comparativelv undeveloped science less tlian 100 vears old, which had always been expected to do uiore than it was capabie of doing. When the first system of weathe'r forecasting met with criticism in the Ilouse of Oomnions for unreliabiiity and becanse forecasts were printed in news papers instead of being used for the benelit only of the wind-driven ships of the navy which was their original purpose, the fonnder of the system, Admiral Fitzroy, committed suicide. The system used today, 80 years after Fitzroy 's death, was basically the same as his and still suffered from the same great handicap — lack of accurate data t'orm which to gauge all the ways an approaching higli or low pressure area miglit beliave. There was usually not enougli Lndlcation to tell when a high or low depression was going to blow it self out of existence as did the depres sion which fooled the Weather Otiice on New Year's Eve. The same unfortunate depression had been delayed off the coast by a large high ahead of it while forecasters watched it in appreheusion. Such delays happened and ended with little warning. Once that depression did reach the coast of the North Island it might have foliowed the coastline down until the centre passed through Cook Strait for weather for nTatious were sometimes deflected b\ mountains and eoastlines. Forecasters could estimate tlie futurt; position of a higli or a low from its past speed and direction but often there was insufficient learning to tell when tlie weather formation was suddenly going to cliange speed or direction or disappear as onr weather was movinsr around the earth from west to east m a changing succession of liighs and lows •which brouglit their own weather conditi'ons within thein. Wellington; was in a far worse posi tion than Svdney for Sydney received data frOili weather observers over the wliole of Australia whereas Wellington had its weather approaching over tlie wide open spaces of . the Tasman and information 011 its passage eould be ob tained only from Lord Howe and Norfolk Islands and an occasional ship -duriug theWar in the Pacifi'c. ' In the Atlantie now weather ships were statioued in their respective areas to give accurate information 011 temperature, pressure, humidity, eloud and so 011. Weather ships gave not only surl'ace information but also reported on conditions up through tlie atniosphere into the stratospheTe. Th'i's important upper air data was gathered by radiosonde equipment. There were at present only two stations in New Zealand where radiosonde was used — Wheiiuajtai and Hokitika. forecasters said New Zealaml needed many more before suiiicient information could be gained on the state of the upper air for reliable forecasting. Hince iniport,s from U.fS.A. were blocked, radiosonde trausmitters had been in sliort suply and according to tlie research otfieer, tliey would sta\ that way until tliey were made locallv at a suffieiently low cost. The trausmitters were sent up attached to balloons wliose position was traced bv radar while the transinitter sent baek automatic signals 011 pressure, temperature and humidity. Aeroplaue flights from day to day were another way of getting upper air data wliicli New Zealand laeked. A dailv meteorological flight from Rongotai during the war gave valuajile insight into Cook Ctrait weather. ''In forecasting, personal knowledge of the topography in all districts was essential, especially in New Zealand where the topography is so varied. 7 ; said Air. Hutchinus. Tlie broken nature.

of the North Island had a v breaking effect on the uniformity of the weather conidtions so the weather forecasts were for niueh smaller districts in the North Island than in the Couth Island wh'ere there ivas not so much variety in the topography and usual weather conditions. Mountain ranges meant many sharp distinctions between cloud and clear and so greatly eomplicated forecasting. kiore important than lack of time iD forecasting was lack of accurate scienti- 1

fic knowledge of New Zealand weather. "In meteorology, as in all science in New Zealand, there is^a great need for a large well equipped research team," said Mr. Huteliings. "Probablv we need it more tlian any other braneh of science beeause other branches of science such as chemistry can make full use of overseas fmdings while the meteorologist m New Zealand has to deal with many weather conditions that are peculiar to this country."