Abstract. Although now over 100 years old, the classification of climate originally formulated by Wladimir Köppen and modified by his collaborators and successors, is still in widespread use. It is widely used in teaching school and undergraduate courses on climate. It is also still in regular use by researchers across a range of disciplines as a basis for climatic regionalisation of variables and for assessing the output of global climate models. Here we have produced a new global map of climate using the Köppen-Geiger system based on a large global data set of long-term monthly precipitation and temperature station time series. Climatic variables used in the Köppen-Geiger system were calculated at each station and interpolated between stations using a two-dimensional (latitude and longitude) thin-plate spline with tension onto a 0.1°×0.1° grid for each continent. We discuss some problems in dealing with sites that are not uniquely classified into one climate type by the Köppen-Geiger system and assess the outcomes on a continent by continent basis. Globally the most common climate type by land area is BWh (14.2%, Hot desert) followed by Aw (11.5%, Tropical savannah). The updated world Köppen-Geiger climate map is freely available electronically in the Supplementary Material Section.

No abstract

Abstract. Although now over 100 years old, the classification of climate originally formulated by Wladimir Köppen and modified by his collaborators and successors, is still in widespread use. It is widely used in teaching school and undergraduate courses on climate. It is also still in regular use by researchers across a range of disciplines as a basis for climatic regionalisation of variables and for assessing the output of global climate models. Here we have produced a new global map of climate using the Köppen-Geiger system based on a large global data set of long-term monthly precipitation and temperature station time series. Climatic variables used in the Köppen-Geiger system were calculated at each station and interpolated between stations using a two-dimensional (latitude and longitude) thin-plate spline with tension onto a 0.1°×0.1° grid for each continent. We discuss some problems in dealing with sites that are not uniquely classified into one climate type by the Köppen-Geiger system and assess the outcomes on a continent by continent basis. Globally the most common climate type by land area is BWh (14.2%, Hot desert) followed by Aw (11.5%, Tropical savannah). The updated world Köppen-Geiger climate map is freely available electronically at https://www.hydrol-earth-syst-sci.net/????.

This paper presents an evaluation of several automated techniques concerned with base flow' separation and recession analyses. Two base flow techniques were considered, one based on a digital filter and the other on simple smoothing and separation rules. A comparison between two commonly used techniques of recession analyses, the correlation method and the matching strip method, was also undertaken. The relative performances of the techniques were evaluated using the results obtained from the daily streamflow records of 186 catchments in southeastern Australia. The work described in this paper was undertaken within the general framework of defining the low-flow characteristics of small rural catchments, the overall objective being the development of a regional model for use on ungauged catchments. k, which is called the recession constant. There appears to be some contradiction in the literature as to who first derived this equation, though it appears that J. Boussinesq, E. Maillet, and R. E. Horton all independently derived the same function around the year 1904 [see Horton, 1933; Werner and Sundquist, 1951; Hall, 1968; Appleby, 1970]. Subsequently, Werner and Sundquist [1951] showed that (1) is the linear solution of the one-dimensional general differential equation governing transient flow in artesian aquifers (the diffusion equation).Barnes [1939] suggested that the three individual components of runoff, overland flow, interflow and groundwater flow, may be distinguished by plotting the logarithms of the flows against time. Recessions that obey (1) plot as a straight line on semilogarithmic graph paper, the gradient of which is equal to the recession constant, and thus the different components may be distinguished by the different straightline segments. Bank storage has also been considered as a fourth store that contributes to streamflow; for large values of time and an infinite aquifer, Cooper and Rorabaugh [ 1963] showed that the recession due to bank storage approaches the simple exponential form of (1). The range of daily recession constants has been found typically to be [e.g., Klaassen and Pilgrim, 1975]: 0.2-0.8 for surface runoff, 0.7-0.94 for interflow, and 0.93--0.995 for base flow. The overlapping ranges reflect the difficulties inherent in identifying a particular recession as being either surface runoff, interflow, or base flow. Alternatively, more complex functions than (1) have been used to describe recession flow. However, after detailed investigation of recession behavior, many authors [e.g., Ineson and Downing, 1964; Nutbrown and Downing, 1976; Anderson and Butt, 1980; Petras, 1986] have concluded that no single linear plot can be constructed for base flow recession. The nonlinearity is a function of factors such as carry-over storage from a prior period of recharge, variations in areal pattern of recharge, channel, bank and flood 1465

Abstract. We analyze the degree of spatial organization of soil moisture and the ability of terrain attributes to predict that organization. By organization we mean systematic spatial variation or consistent spatial patterns. We use 13 observed spatial patterns of soil moisture, each based on over 500 point measurements, from the 10.5 ha Tarrawarra experimental catchment in Australia. The measured soil moisture patterns exhibit a high degree of organization during wet periods owing to surface and subsurface lateral redistribution of water. During dry periods there is little spatial organization. The shape of the distribution function of soil moisture changes seasonally and is influenced by the presence of spatial organization. Generally, it is quite different from the shape of the distribution functions of various topographic indices. A correlation analysis found that ln(a), where a is the specific upslope area, was the best univariate spatial predictor of soil moisture for wet conditions and that the potential radiation index was best during dry periods. Combinations of ln(a) or In(a/tan(/3)), where/3 is the surface slope, and the potential solar radiation index explain up to 61% of the spatial variation of soil moisture during wet periods and up to 22% during dry periods. These combinations explained the , 1995;Willgoose, 1996; Bl6schl, 1999]. This paper examines (1) the degree of spatial organization of soil moisture in a small catchment during different seasons and (2) how well that organization can be predicted using terrain indices.Hydrologic processes can vary in space in an organized way or randomly or in a combination of the two [Gutknecht, 1993; Bl6schl et al., 1993; Bl6schl, 1999]. We use "randomness" to refer to variability that is not predictable in detail but that has predictable statistical properties, and "organization" to refer to regularity or order. Spatial organization implies variation characterized by consistent spatial patterns [Bl6schl, 1999]. In the context of this paper most of the organization is related to topography. Bl6schl [1999] noted that natural systems can vary from completely disorganized (disordered, random) to highly 797

An important determinant of the mechanics of running is the effective vertical stiffness of the body. This stiffness increases with running speed. At any one speed, the stiffness may be reduced in a controlled fashion by running with the knees bent more than usual. In a series of experiments, subjects ran in both normal and flexed postures on a treadmill. In other experiments, they ran down a runway and over a force platform. Results show that running with the knees bent reduces the effective vertical stiffness and diminishes the transmission of mechanical shock from the foot to the skull but requires an increase of as much as 50% in the rate of O2 consumption. A new dimensionless parameter (u omega 0/g) is introduced to distinguish between hard and soft running modes. Here, omega 0 is the natural frequency of a mass-spring system representing the body, g is gravity, and u is the vertical landing velocity. In normal running, this parameter is near unity, but in deep-flexed running, where the aerial phase of the stride cycle almost disappears, u omega 0/g approaches zero.

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Many parameters of gait and performance, including stride frequency, stride length, maximum speed, and rate of O2 uptake are experimentally found to be power-law functions of body weight in running quadrupeds. All of these parameters are reasonably easy to measure except maximum speed, where the question arises whether one means top sprinting speed or top speed for sustained running. Moreover, differences in training and motivation make comparisons of top speed difficult. The problem is circumvented by comparing animals running at the transition between trotting and galloping, a physiologically similar speed. Theoretical models are proposed which preserve either geometric similarity, elastic similarity, or static stress similarity between animals of large and small body weights. The model postulating elastic similarity provides the best correlation with published data on body and bone proportions, body surface area, resting metabolic rate, and basal heart and lung frequencies. It also makes the most successful prediction of stride frequency, stride length, limb excursion angles, and the metabolic power required for running at the trot-gallop transition in quadrupeds ranging in size from mice to horses.