Wild Tobago

It’s not too early to begin preparing for summer sargassum.   Dr Anjani Ganase reviews the latest Sargassum White Paper generated by the United Nations Environmental Programme. The big picture requires trans-Atlantic cooperation - West Africa and Brazil   to fully understand the annual sargassum influx .   Since 2011 and persisting to today, sargassum has been washing up on beaches and coasts of the Caribbean and South and Central America as regular summer events. The highest amounts to date were 27 million tonnes (estimated) of sargassum washed up in 2018; with 20 million tonnes in 2019.   Amazon and Sahara While the two species of sargassum ( S. natans and S. fluitans ) that wash up on our shores naturally occur and grow in oceanic gyres (in the mid-Atlantic), the excessive amount of algal blooms transported is new. Scientists are now certain that these blooms are the result of increased nutrient outflow from the Amazonian basin, mixed...

  Unusually high temperatures on the west coast of North America, more violent tropical storms are just some indicators of climate change. What happens when changes become irreversible? Dr Anjani Ganase considers a few indicators of ecosystems approaching tipping point.     Tipping points are the environmental conditions beyond which an ecosystem can no longer cope with change. There is no going back when a tipping point is reached. The result is an irreversible shift to an alternative ecological state. Such shifts are usually associated with loss in biodiversity and changes in ecosystem services. Climate change drives unstable environmental conditions; and push organisms beyond their thresholds of tolerance; leading to mass die off and no recovery in a permanently transformed environment. Scientists are concerned about the global reach of climate change driving ecological tipping points that will permanently change the biomes that we depend on to survive.   Th...