Climate in the North Pacific and North American sectors has experienced interdecadal shifts during the twentieth century. A network of recently developed tree-ring chronologies for Southern and Baja California extends the instrumental record and reveals decadal-scale variability back to 1661. The Pacific decadal oscillation (PDO) is closely matched by the dominant mode of tree-ring variability ...

A new approach to cointegration developed by Enders et al. (Cointegration tests using instrumental variables with an example of the U.K. demand for money. Unpublished working paper. http://wenders.people.ua.edu/time-seriesmethods.html, 2008) is applied to long-span, high-frequency data to test for purchasing power parity in the Mexico–US real exchange rate. Overall the empirical results suggest...

This article briefly describes key features of the 1994 Cairo Plan of Action and US population assistance, and identifies US efforts to implement the Cairo agenda. US leadership and funding play a key role in global population stabilization issues. Opponents of population assistance in recent years have been undermining the US position as a world leader in global stabilization and restricting...

Change in global aerosol composition since preindustrial times K. Tsigaridis, M. Krol, F. J. Dentener, Y. Balkanski, J. Lathière, S. Metzger, D. A. Hauglustaine, and M. Kanakidou Environmental Chemical Processes Laboratory, Department of Chemistry, University of Crete, P.O. Box 2208, 71003 Voutes, Heraklion, Greece Institute for Marine and Atmospheric Research, Utrecht, The Netherlands JRC, Ins...

4 M. Petrillo, P. Cherubini, G. Fravolini, M. Marchetti, J. Ascher, M. Schärer, H.-A. Synal, D. 5 Bertoldi, F. Camin, R. Larcher, and M. Egli 6 7 Department of Geography, University of Zurich, 8057 Zurich, Switzerland 8 WSL Swiss Federal Institute for Forest, Snow and Landscape Research, 8903 Birmensdorf, 9 Switzerland 10 Laboratory of Ion Beam Physics, ETH Zurich, 8093 Zurich, Switzerland 11 D...