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CONTRIBUTION OF UPPER-AIR OBSERVING SYSTEMS AND REMOTE SENSING TECHNOLOGIES TO THE ACCURACY OF METEOROLOGICAL FORECASTS Bataze James and Khalid Muwembe Department of Meteorology P. o . Box 7025, Kampala - Uganda Email: [email protected] Introduction: Observations are the bedrock of weather forecasting as these records help to keep track of the weather changes. For centuries people have made observations and forecast the weather using observed patterns of events on both land and sea surfaces plus signs in the atmosphere This ancient and primitive methods of forecasting weather not only misled the forecasters of those days but also produced inaccurate forecasts, as none of the weather conditions from the upper levels of the Introduction CONT… Until the middle of the 17th Century, very little was known about the physical characteristics of the atmosphere above the surface. People knew that it got colder with height but not until the invention of the barometer and thermometer was it possible to make any measurements. The atmospheric disturbances are key determinant to an accurate forecast, hence a good knowledge of the weather conditions in the upper levels of the atmosphere greatly affect what happens at the surface of the Earth. Introduction CONT… The quality of meteorological forecasts issued out have been improving since the beginning of the upper air observing systems using pilot balloons with radiosondes attached, aircrafts, wind profilers and remote sensing technologies of satellites and radar.. Also the prediction potential of weather forecasters was enhanced by the inception of remote sensing technologies by use of meteorological satellites and radars Introduction CONT… From the observing system experiments carried out at European Centre for Medium Range Weather Forecasts (ECMWF) to assess the relative contribution from various terrestrial observing systems to the global Numerical Weather Prediction, It was found out that radiosondes, aircraft observations, wind profilers, satellites and radars provide vital information used in the making of an accurate meteorological forecast( Jean-Noelthepaut and Graeme Kelly 2007, ) . Introduction CONT… According to research carried out so far upper air observing system and remote sensing technology have been found to be the most effective observing systems in the safeguarding of life and property through accurate forecasting and prediction) www.eohandbook.com). It enables the detection, tracking, monitoring and giving warnings of severe weather phenomena such as local storms, tornadoes, tropical cyclones, typhoons, hurricanes, volcanic eruptions, tsunamis and many others that destroy life and property.( EO Handbook of observations Problem statement Of recent there has been debate among meteorologists and other climate scientists about the contribution of upper air observing systems and remote sensing technologies in the weather forecasting. Objectives of the study The main objective of this study was to investigate the contribution of upper air observing systems and remote sensing technologies in the preparation of an accurate meteorological forecast. Study Area: The study area for this research is the evolution of observing systems and weather forecasting, that have been used for many centuries to forecast weather. Right from ancient times people have been observing and trying to forecast weather informally and formally, and in 650 BC, the Babylonians predicted the weather from cloud patterns as well as astrology. Study Area contd…. In about 340 BC, Aristotle described weather patterns in meteorologica, and later Theophrastus compiled a book on weather forecasting called the book of signs. At around 300BC the Chinese and Indian astronomers developed weather prediction methods. Later in 904 AD, Ibn Wahshiyya’s Nabatean Agriculture discussed the weather forecasting of atmospheric changes and signs from the planetary astral alterations; signs of rain based on observation of the lunar phases; and weather forecasts based on the movement of winds. Study Area contd…. Ancient weather forecasting methods usually relied on observed patterns of events, termed as pattern recognition, for example it might be observed that if the sunset was particularly red, the following day often brought fair weather In Europe upper air observation began as early as 1749 with the use of a kite, the kites carried aloft meteorological instruments or “meteorographs “ that recorded pressure, temperature, and relative humidity data on a clock driven chart recorder. Study Area contd…. And in 1780`s with the invention of hot air balloon in France, it enabled scientists to ascend aloft taking with them more weather instruments to investigate the structure and chemistry of upper atmosphere. How ever the use of kites and hot air balloons had several disadvantages such as the average altitude was low, data could not be readily available for weather forecasting, observations could only be taken in good weather, and there was danger of the kite breaking away and endangering lives and property Study Area contd…. In 1920`s saw the advent of aircrafts being used for upper air observations and carrying of meteographs The inability of the kites, balloons and aircrafts to operate in all weather and provide data in real time helped foster the development for the radio transmission of upper air data. In the early 1930`s the first unmanned balloons carrying radio mateorographs or radiosondes started being flown in the stratosphere to carry out observations of upper air atmosphere. Study Area contd…. With more advances in upper-air observing technology saw the development of remote- sensing observing systems such as satellites, radars, wind profilers plus the placement of temperature and water vapour sensors on commercial aircraft . In the late 1950`s saw the launching of the of the first satellite, but the first satellite completely dedicated to satellite meteorology called TIROS ( Television and Infrared Observational Satellite) was launched on 1st April 1960, and this brought a new chapter in upper-air observations because of their almost global coverage. . Study Area contd…. Satellites also provide data on cloud development, information on temperatures at the surface and cloud tops, Currently satellite systems monitor the evolution and impact of El Nino episodes, natural droughts, vegetations cycles and mappings, the ozone hole, solar fluctuations, changes in mountain snow cover, sea ice sheets, sea surface temperatures, floods, forest fires, deforestations, coastal zones, urban development, volcanic eruptions, plate motions and more(observation of climate by earth orbiting satellites –(CEOS EO Handbook on Observations. www.eohandbook.com). Study Area contd…. A good example of how satellites can help to monitor volcanic eruptions was in April 2010 when it was possible to track the movement of ash clouds from the Icelandic volcano Eyjafjallajökull, and meteorological offices were able to give accurate warnings and forecasts to the aviation industry. Data source: The source of data for this research has been achieves of meteorological information, papers written by other researchers, reports, manuals and internet. Earth Observing Systems and Networks: Current Earth observing systems include networks of satellite- borne and ground-based sensors-including ocean buoys, weather stations and atmospheric radiosondes, that provide important parameters relating to land, ocean and atmospheric processes. The main Earth observing networks and international programmes that coordinate the different observations include: Earth Observing Systems and Networks contd…. The main Earth observing networks and international programmes that coordinate the different observations include: World Weather Watch (WWW), Global Observing System (GOS), Global Telecommunication System (GTS), the Global Data Processing System.(GDPS), Global Atmosphere Watch (GAW), Global Ocean Observing System (GOOS), Global Climate Observing System (GCOS), Committee on Earth Observation Satellites, (CEOS), Global Sea Level Observing System (GLOSS), Global Terrestrial Observing System (GTOS). Discussion of results From this research it shows that right from the period people started making observations and weather forecasting, the early observing methods were based on pattern recognition of invents on land, sea and the atmosphere such the lunar phases, position of stars, colour of the sky, movement of winds and sea surfaces From this study it has been found out that since the inception of upper air observing system in 18th century and remote sensing technologies in the 20th century the accuracy of meteorological forecasts have greatly improve With the application of satellite meteorology it has become easy to identify and track severe weather disaster such as storm storms and give warnings that help to protect life and property. Conclusion: From this study it has been found out that the upper air observing system and remote sensing technology have really contributed greatly to accuracy of meteorological forecasts given out the world over. Recommendations: I recommend that further research need to be done to find out the relative contributions from various terrestrial observing systems to the Numerical Weather Predictions Acknowledgement I thank my co-author for his contribution towards this research and all those gave given me assistance when writing this paper. THE END THANK YOU VERY MUCH FOR LISTENING TO ME.