HISTORICAL THERMOMETER EXPOSURES IN AUSTRALIA

There is ample contemporary evidence that most meteorological thermome ters in Australia were not exposed in Stevenson screens until very lat e in the nineteenth century, and in many places not until well into th e twentieth century. There is also evidence, from a long-running compa rison at Adelaide, that mean temperatures in a Stevenson screen are lo wer than in an open stand in Australian conditions. Thus, there are st rong grounds for expecting that nineteenth century, and some early twe ntieth century, Australian temperatures are biased warm, relative to m odem exposures.