Introduction - Principles of Chemical Separations with Environmental Applications - page 9

note acid-rain damage to plants and materials. He proposes detailed procedures
for the collection and chemical analysis of precipitation.

1911 English scientists C. Crowther and H. G. Ruston demonstrate that acidity of

precipitation decreases the further one moves from the center of Leeds, England.
They associate these levels of acidity with coal combustion at factories in Leeds.

1923 American scientists W. H. MacIntyre and I. B. Young conduct the first detailed

study of precipitation chemistry in the United States. The focus of their work is
the importance of airborne nutrients to crop growth.

1948 Swedish scientist Hans Egner, working in the same vein of agricultural science

as MacIntyre and Young, set up the first large-scale precipitation chemistry
network in Europe. Acidity of precipitation is one of the parameters tested.

1954 Swedish scientists Carl Gustav Rossby and Erik Eriksson help to expand Egner's

regional network into the continent-wide European Air Chemistry Network .
Their pioneering work in atmospheric chemistry generates new insights into the
long-distance dispersal of air pollutants.

1972 Two Canadian scientists, R. J. Beamish and H. H. Harvey, report declines in fish

populations due to acidification of Canadian lake waters.

1975 Scientists gather at Ohio State University for the First International Symposium

on Acid Precipitation and the Forest Ecosystem .

1977 The UN Economic Commission for Europe (ECE) sets up a Cooperative

Programme for Monitoring and Evaluating the Long-Range Transmission of
Air Pollutants in Europe .

1979 The UN's World Health Organization (WHO) establishes acceptable ambient

levels for SO 2 and NO x . Thirty-one industrialized nations sign the Convention
on Long-Range Transboundary Air Pollution under the aegis of the ECE.

1980 The US Congress passes an Acid Deposition Act providing for a 10-year acid-

rain research program under the direction of the National Acid Precipitation
Assessment Program .

1980 The United States and Canada sign a Memorandum of Intent to develop a bi-

lateral agreement on transboundary air pollution, including “the already serious
problem of acid rain.”

1985 The ECE sets 1993 as the target date to reduce SO 2 emissions or their trans-

boundary fluxes by at least 30% from 1980 levels.

1986 On January 8, the Canadian and US Special Envoys on Acid Rain present a joint

report to their respective governments calling for a $5 billion control technology
demonstration program.

1986 In March, US President Ronald Reagan and Prime Minister Brian Mulroney of

Canada endorse the Report of the Special Envoys and agree to continue to work
together to solve the acid-rain problem.

1995 An Intergovernmental Panel on Climate Change, representing over 2,000 scien-

tists from over 50 countries, concludes that “the balance of evidence suggests
there is a discernable human influence on global climate.” They also list some