The impact of rapid urbanization on pan evaporation in phoenix. Arizona

Abstract

Rapid urbanization in Phocnix, Arizona over the past few decades has been associated with large increases in local temperature and wind speed values, and decreases in local dew point and relative humidity levels. In this study, the impact of these urban-induced climatic changes on long-term pan evaporation rates is identified. The results indicate an increase from 1917 to 1985 in the local pan evaporation in all months of the year. Following a long period of generally increasing pan evaporation levels, a sharp jump in the pan measurements occurred in the late 1960s. This pronounced discontinuity in the long-term record appears to be associated with the construction of a nearby regional shopping centre in 1968. Given widespread similar land-use changcs throughout this rapidly growing descrt city, and given the well-documented changcs in local climatic conditions, potential evapotranspiration increases are probably occurring throughout much of the metropolitan area.

On climate variability in Northeast of Brazil

“…This is consistent since at low relative humidity the evaporative demand of atmospheric increases and, consequently, the variables under its influence are also increased. Balling and Brazel (1987) also found evidence for an increase in the local pan evaporation in all month of year, in Phoenix, Arizona. The decreasing trend in relative humidity in the dry-season was most accentuated in the Campos Sales station (Table 3).…”

“…Many investigators have studied climatic changes in various regions of the world including: United States (Balling and Brazel, 1987;Comrie and Broyles, 2002); Philippines (Jose et al, 1996); Bahrain (Elagib and Abdu, 1997); Europe (Arnell, 1999;Velichko et al, 2002); Kenya (Kipkorir, 2002); Arab Region (Abahussain et al, 2002); Taiwan (Chang, 2002;Yu et al, 2002); Israel (Cohen et al, 2002); and Italy (Moonen et al, 2002). On the other hand, Nimer (1988) and Silva et al (1998) studied the problems of desertification and rainfall trends in Brazil, respectively.…”

“…However, climate variability and climate change have been researched recently based on the analysis of different climatic variables. The most common are: class A pan evaporation (Balling and Brazel, 1987;Cohen et al, 2002); the aridity index (Elagib and Abdu, 1997); and reference evapotranspiration (Hupet and Vanclooster, 2001;Kipkorir, 2002). Indeed, temperature and rainfall time-series are much used in climate variability analysis (see e.g.…”

Creating the park cool island in an inner-city neighborhood: heat mitigation strategy for Phoenix, AZ

“…The climatic consequences of anthropogenic surface cover changes at the regional scale are well understood. The replacement of natural covers with the urban fabric results in significantly higher nighttime temperatures in built-up areas compared to the surrounding rural environment (Balling and Brazel 1987;Lowry 1967;Oke 1997). Reintroducing urban green spaces with canopied vegetation can alter surface and near-surface energy flows and act as wind tunnels or barriers, potentially reducing the intensity of UHIs (Barradas et al 1999;Grimmond et al 1996;Oke 1989).…”

Effects of three landscape treatments on residential energy and water use in Tucson, Arizona

“…These "granitescapes" conserve water and reduce maintenance, but they also create hot arid microclimates that can increase building cooling requirements. For instance, the conversion of irrigated croplands to largely impervious urbanized landscapes in Phoenix, Arizona, has been associated with large increases in local temperatures and pan evaporation [ 17 ].…”