Geoscience Reference
In-Depth Information
3.1 Introduction
Comprehensive international research programmes and reviews have firmly established that
human activities are substantially impacting the total environment, including the ocean, and
are triggering global and regional changes in the physical, chemical, and biological condi-
tions which affect ecosystems and human societies. These programmes include the Interna-
tional Geosphere-Biosphere Programme (IGBP), the Large Marine Ecosystem Programme
(LME), activities of the Intergovernmental Oceanographic Commission (IOC) and World
Heritage Convention of UNESCO, as well as integrated assessments of the Intergovern-
mental Panel on Climate Change (IPCC) and the United Nations Environment Programme
As a consequence of the growing needs of the increasing human population, diverse
pressures on the marine environment have increased markedly over past decades. These in-
clude offshore oil and gas exploration and exploitation (e.g. into deeper and more hazardous
areas of the Arctic Basin), expansion of fisheries into new areas (e.g. the Southern Ocean
krill fisheries), transportation and shipping (e.g. across previously ice-covered areas of the
Arctic Basin), offshore extraction of renewable energy, aquaculture production, enhanced
use of the coastal zone for urbanization, land reclamation, infrastructure installations, ports
and transportation, and recreation and tourism. Taken together these factors constitute a
global change parallel to the population growth since the 1950s, with large consequences for
our physical environment. However, what of all these factors constitutes
significant
change?
considered significant when they affect the biosphere, including humans'. This definition
agrees in principle with the IGBP and LME approach. Observations and model simulations
show that impacts of climate change on the ocean include the redistribution of oceanic water
mass boundaries and habitats, and identify the need for time-series observations over a wide
range of ocean zones that will permit science-informed policy decisions.
