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The relationship between annual rainfall totals and gauge elevation over Great Britain is re-examined using the recently developed technique of geographically weighted regression (GWR). This enables the spatial drift of regression parameters to be identified, estimated and mapped. It is shown that the rate of increase of precipitation with height, or height coefficient, varies from around 4.5 mm/m in the northwest to almost zero in the southeast. There is a particularly rapid change in this value across the English Midlands. The predicted sea level precipitation varies from 1250 mm to less than 600 mm in much the same way.

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The increasing availability of very high spatial resolution data using the unit post code as its geo-reference is making possible new kinds of urban analysis and modelling. However, at this resolution the granularity of the data used to represent urban functions makes it difficult to apply traditional analytical and modelling methods. An alternative suggested here is to use kernel density estimation to transform these data from point or area 'objects' into continuous surfaces of spatial densities. The use of this transformation is illustrated by a study in which we attempt to develop a robust, generally applicable methodology for identifying the central areas of UK towns for the purpose of statistical reporting and comparison. Continuous density transformations from unit post code data relating to a series of indicators of town centredness created using ArcView are normalised and then summed to give a composite 'Index of Town Centredness'. Selection of key contours on these index surfaces enables town centres to be delineated. The work results from a study on behalf of DETR.

AISSTKACT. If glacial till contains more than a certain minimum boulder content, it is dilatant and requires a much larger stress to initiate shear deformation than to sustain il. If the stress level at the glacierlerrain interface drops below a certain critical level, or the till reaches its critical boulder-content density, then the till beneath the glacier packs into stable obstructions. These are shaped into streamlined forms by the giacier and are found distributed at random i" drumlin fields. Due to drumliii coalescence there is a normal distribution of drumlin axes about the direction of ice movement. RESUME. La formation rt mor/jlurlogir de drumlins et four repartition cl orientation en champs de drumlins. Si mi argile a blocaux contient plus d'une certaine quantite minimum de blocaux. il est dilatable et exige une plus grande tension pour debuter line deformation par cissaillement que pour 1c soutenir. Si le niveau de tension entre le glacier et le terrain descend au-dessous d'un certain niveau critique, ou si l'argile a blocaux atteint sa densite critique de blocaux, alors l'argile a blocaux au-dessous du glacier s'agglomere et forme des obstacles stables de formes carenees et distributes au hasard en champs de dnmihns. A cause de leur coalescences, les axes des drumlins s'alignem avec la direction ciu mouvement glaeiaire en une repartition normale.