Modelling lapse rates in the maritime uplands of Northern England: implications for climate change

Recent high-resolution meteorological data from the Pennines of northern England are used to study temporal variation in surface temperature lapse rates. A regression approach uncovers significant relationships between lapse rates and solar input, mean temperature, vertical mixing (modeled through wind speed), and atmospheric moisture (specific and relative humidity). Prediction of lapse rates is successful, especially during spring, summer, and autumn, with mean r² above 0.66 (66%). Lapse rates are shallower for higher mean temperatures and for a moister atmosphere, but steeper under increased daytime solar input. At night windy conditions increase lapse rate. In addition, synoptic influences upon lapse rate are investigated. The diurnal lapse rate cycle increases under anticyclonic influences and when flow strength is weak. Southerly airflows have shallower lapse rates. Application of the above to consider possible climate change suggests that lapse rates should be shallower in a warmer moister atmosphere, but that synoptic controls are equally influential.