Nagoya, which is located in the central part of Japan, is one of the fastest growing cities in Japan. Like other big cities, the problems associated with urban heat islands are very serious in the Nagoya metropolitan area. The increase in the annual-mean surface air temperature for the last 100 years is 2.7°C, and a further increase will likely occur in the future. In this study, an attempt to project a thermal environment in the summers of the 2070s in the Nagoya metropolitan area was conducted by using a regional atmospheric model, WRF. Pseudo global warming data generated by a general circulation model, which was based on the A2 scenario of IPCC Forth Assessment Report, were used for the initial and boundary conditions in the WRF computations. We also carried out a numerical investigation of the present thermal environment and compared the difference between the present and future status of the thermal environment in the Nagoya metropolitan area. Furthermore, numerical experiments involving the introduction of several countermeasures to improve the projected thermal environment in the summers of the 2070s were performed, and the effects of each countermeasure were quantitatively investigated.
