Annual, daily and diurnal variation of Urticaceae pollen in North-central London
Annual differences in cumulative counts of Urticaceae pollen are found to relate primarily to the weather conditions during the pollen formative period (April and May) and secondarily to the weather prevailing during the season itself. Relative humidity, temperature, wind velocity and precipitation emerge as the most influential variables in the analysis of daily variations but their relative importance varies between years. Diurnal patterns in concentrations show general peaks occurring in the early evening but the severity and exact timing of these relates closely to wind direction. The implications of these results are considered in the context of forecasting.
Key wordsannual daily diurnal meteorological factors Urticaceae
- Burton R.M., (1983) —Flora of the London Area. London Natural History Society.Google Scholar
- Moseholm L., Weeke R.E., Petersen B. (1987) —Forecast of pollen concentrations of Poaceae (Grasses) in the air by time series analysis. Pollen et Spores Vol.XXIX: 305–322.Google Scholar
- Norris-Hill J., Emberlin J., (1991) —Diurnal variation of pollen concentration in the air of north-central London. Proceedings of the 4th International Conference on Aerobiology, Stockholm 1990.Google Scholar