Power stations, ships and air traffic are among the most potent greenhouse gas emitters and are primarily responsible for global warming. Iron salt aerosols (ISAs), composed partly of iron and chloride, exert a cooling effect on climate in several ways. This article aims firstly to examine all direct and indirect natural climate cooling mechanisms driven by ISA tropospheric aerosol particles, showing their cooperation and interaction within the different environmental compartments.

A reconstruction of changes in ocean oxygenation throughout the last glacial cycle shows that respired carbon was removed from the deep Southern Ocean during deglaciation and Antarctic warm events, consistent with a prominent role of reduced iron fertilization and enhanced ocean ventilation, modifying atmospheric carbon dioxide concentrations over the past 80,000 years.

Carbon dioxide removal (CDR) approaches are efforts to reduce the atmospheric CO2 concentration. Here we use a marine carbon cycle model to investigate the effects of one CDR technique: the open ocean dissolution of the iron-containing mineral olivine. We analyse the maximum CDR potential of an annual dissolution of 3 Pg olivine during the 21st century and focus on the role of the micro-nutrient iron for the biological carbon pump.

Original Source

The Conference of the Parties (COP) of the Convention on Biological Diversity (CBD) first turned its attention to geoengineering at its ninth meeting in 2008, in the context of ocean fertilization.

Fertilization of the ocean by adding iron compounds has induced diatom-dominated phytoplankton blooms accompanied by considerable carbon dioxide drawdown in the ocean surface layer. However, because the fate of bloom biomass could not be adequately resolved in these experiments, the timescales of carbon sequestration from the atmosphere are uncertain.

The discovery that marine algal blooms deposit organic carbon to the deep ocean answers some — but not all — of the questions about whether fertilizing such blooms is a viable strategy for mitigating climate change.

Countries move from labs to seas to study the implications of ocean acidification. On a pleasant morning when fifty-four-year-old Australian marine diver David Hannan was gearing to plunge into the deep sea, a bunch of American scientists were ready to set sail for the Arctic Ocean. In another corner of the world at Dona Paula in Goa oceanographers were contemplating plans to measure coastal pH along the entire Indian coastline.

For full text: http://www.downtoearth.org.in/content/changing-basic-nature

Dust is all that's needed to plunge the world into an ice age. When blown into the sea, the iron it contains can fertilise plankton growth on a scale large enough to cause global temperatures to drop. The finding adds support to the idea of staving off climate change by simulating the effects of dust - perhaps by sprinkling the oceans with iron filings.

The seasonal variability of phytoplankton biomass in the Arabian Sea, though a well researched topic, its inter-annual variability is less explored and understood. Analysis of the satellite-derived chlorophyll pigment concentration in the Arabian Sea during 1997

In a world plagued by the effects of climate change, ocean iron fertilization and other geoengineering techniques1 could help to respond and adapt to this global environmental crisis.

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