Loading...
The Rural Voice, 1993-05, Page 14"Our experience assures lower cost water wells" 92 YEARS' EXPERIENCE Member of Canadian and Ontario Water Well Associations • Farm • Industrial • Suburban • Municipal Licensed by the Ministry of the Environment DAVIDSON WELL DRILLING LTD. WINGHAM Serving Onrano Since 1900 519-357-1960 WINGHAM 519-886-2761 WATERLOO VENTILATION MI IN ;rx.h.... / i AXIS -AIR BLENDER -' Uniform Temperature - o Reduces Drafts -o Automatic System - 0 Easy Maintenance - o Corrosion Resistant -0 SERVICE for Martin -Air PHONE 519-345-2258 AXIS PRODUCTS LTD., 5 Main Street, Brodhagen, Ontario Canada NOK 1130 Dealer enquiries welcome 10 THE RURAL VOICE Robert Mercer Global warming — Global cooling — Which? At the end of March I attended a special symposium discussing soybeans in Canada over the last 100 years. However, one of the most interesting pre- sentations was looking forward and discussed weather, a topic that is always of interest to the farm commu- nity. Dr. Tim Ball from the Univ- ersity of Winni- peg, who is a professor of Cli- matology, took a look at long term weather patterns and basically said that what we are experiencing today is increased variability within stable limits of weather extremes. It is not abnormal. On the subject of global warming Dr. Ball said that the effect of the large volcanic eruption at Mt. Pinatu- bo in the Philippines last year was such that it offset any influence of global warming. That single giant eruption was the cause of a two -deg- ree cooling around the globe over the 12 -month period following the erup- tion. What it effectively did in 1992 was to cause a 30 -degree-day drop in temperature, and an increase in cloud cover. For 1993 Dr. Ball expects half of the volcanic dust in the atmos- phere to be lost, and that this year the effect will be to lower the extreme by 15 degree days below normal, or only half as bad as last year. So, Dr. Ball says, there will be more sunlight and it will be warmer than in 1992. Another side effect of the volcanic eruption from the dust is the sulphur pumped into the air. When combined with moisture the coloured droplets filtered out the yellow rays of the sun, and this is detrimental to growth and photosynthesis, especially for soybeans. He also spoke very directly over the concern being expressed about a hole in the ozone layer. First of all, he said there is no hole. It is thinner, just three per cent thinner, whereas the normal variability that has been measured in ozone is in the range of 15 per cent. The ozone problem is self-correcting, according to Dr. Ball. In terms of the weather outlook he suggests that the most important factor to watch this year will be the position of the jet stream. So far the polar jet stream has been lower (further south) than normal. This tends to suggest lower temperatures than might otherwise be expected. This year there is another volcano to watch, also in the Philippines. In this case the volcano is bulging on the side, so although the eruption may be significant, if it does not blast upward, but rather sideways, the ash will not go directly into the higher atmosphere and will therefore not have such an effect on weather. When listening or reading about weather phenomena Dr. Ball cautions the public over the idea that any one aspect — such as the EI Nitio — has the answer to future weather patterns. The subject is so complex and inter- related that it is very difficult to make any reliable forecasts or projections. The single most important aspect to Dr. Ball is "water vapour" or clouds. This is far more important than the amount of CO2 in the air with respect to temperature and the global warm- ing effect. He also noted that for all the research that has gone into global warming to prove the temperatures have gone up 0.5°C, it now appears as if 0.4°C of that change can be accounted for by the encroachment of cities to, and past, the spots where temperature is and has been measur- ed. Cities create their own warmth and this has affected the temperature readings as cities have spread out and around the meteorological offices where temperatures have been recorded for the last 50 to 80 years. As a closing comment, Dr. Ball noted in his talk that it was only in 1976 that researchers were calling for global cooling and the next ice age, which Dr. Ball sees coming, but not for 23,000 years!0 Robert Mercer is editor of the Broadwater Market Letter, a weekly commodity and policy advisory letter from Goodwood, Ontario LOC 1A0.