Geoscience Reference
In-Depth Information
1.2 Realizing that global change is largely determined by
humans
We live in a planet the biophysical processes of which are increasingly impacted upon by
human activity. Human uses of ocean areas have impacts at multiple scales.
Fisheries and aquaculture, shipping, recreation, energy, water extraction, military activ-
ities, underwater cables, scientific research, and mining represent the main uses. These all
have potential and actual impacts on the marine environment, in the form of physical and
chemical alteration of habitat features, biodiversity erosion and loss, climate change, ocean
acidification, unsustainable depletion of species stocks, alteration of dispersal patterns, as
well as social impacts such as disruption of local livelihoods due to the collapse of local nat-
ural resources, competition between industrial versus locally based fishing and aquaculture
activities, and unsustainable tourism plans and initiatives.
Therefore there appears to be a clear need to reconcile human uses of ocean areas and
resources therein with the imperative of preserving the functional integrity of the world
ocean so as to ensure healthy and productive oceans for current and future generations. The
first step in this direction is to fully realize the value of the oceans.
Marineecosystems providearoundtwo-thirdsoftheglobalaggregate ofecosystem ser-
vices through the provision of seafood and other natural resources, worth trillions of dollars
per annum, regulation of the Earth's climate, and the modulation of global biogeochemical
cycles, water quality maintenance, opportunities for renewable energy production from the
sea, trade-related services, and cultural and aesthetic benefits. There is a need to capture the
broader change in social welfare which has derived from management intervention related
to the marine environment.
Change in ecosystems can lead to welfare benefits even in the absence of a market
price, hence the need for valuation methodologies in economics to value non-marketed be-
nefits deriving from nature. The presumption that a cost or benefit arising in the near fu-
ture affects our welfare more than that same cost or benefit arising in the distant future, also
