sampled households and their economic activities. The questionnaire also included a module for perceptions and adaptations of households to climate change.

# **_3.2 Data description_**

# _Climate data_

In addition to the household data, the study also makes use of climate data (temperatures, soil wetness indices and precipitation). Satellite data were provided by the US Department of Defense. The data values were derived from a set of polar orbiting satellites that are equipped with sensors to detect microwaves through clouds and estimate surface temperature and surface wetness (Basist et al. 1998, 2001; Weng & Grody 1998). The other set of climate data were obtained from the Africa Rainfall and Temperature Evaluation System -ARTES (World Bank 2003). This dataset, created by the National Oceanic and Atmospheric Association’s Climate Prediction Center, is based on ground station measurements of precipitation and minimum and maximum temperature. The data were constructed from a base with data for each month of the survey year and for morning and evening. The monthly means were estimated from approximately 14 years of data (1988–2003) to reflect long-term climate change.

To save space in Tables 5 and 6, we present only the estimated mean annual and seasonal values for all climate variables. Table 5 summarizes the ARTES temperature and precipitation data. The long-term mean annual ARTES temperature is estimated at about 22 _°_ C, the long rains temperature at 21 _°_ C and the short rains at 22 _°_ C, showing that there are no major variations in seasonal temperatures in Kenya (because the country is located across the equator). The three-month seasonal values show the lowest mean temperature as about 20 _°_ C (winter, June–August) and the highest as about 23 _°_ C (summer, March–May). The variations across provinces (results not presented), show Coast Province as having the highest temperatures among the selected provinces, with an annual mean of 25 _°_ C. The lowest temperature observed for this province is for winter at 24 _°_ C. Central Province has the lowest temperatures, with an annual mean of 20 _°_ C, and the lowest long rain mean temperature, 18 _°_ C.

The ARTES precipitation data in Table 5 show the mean annual precipitation for the whole country as 85mm, with a standard deviation of 19mm. The long rains mean (at 91mm) is significantly higher than the short rains mean (81mm).<sup>5</sup> This implies that there are significant seasonal variations in mean precipitation in Kenya. This variation is also observed across provinces, with Nyanza and Western Province recording the highest long-term mean precipitation values (112mm for Nyanza and 110mm for Western Province, but the long rains reach a high of 129mm and 136mm for the two provinces respectively). Coast Province is observed to have the lowest precipitation (an annual mean of 65mm, with long rains at 76mm and short rains at 51mm). In the empirical analysis, we find that defining winter as June– August and fall as December–February gives us the climate model that best fits the data.

> 5 Though long rains fall between March and May and short rains between October and December, there is the extended cropping season. Long rain crops planted in early March are harvested in August. Farms are then prepared and planted in September and the crops harvested in February.

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