Coming-out

The process of relocating people from New Orleans should start immediately, as the city has reached a “point of no return” that will see it surrounded by the ocean within decades due to the climate crisis, a stark new study has concluded. Ongoing sea-level rise and the rampant erosion of wetlands in southern Louisiana will swallow up the New Orleans area within a few generations, with the new paper estimating the city “may well be surrounded by the Gulf of Mexico before the end of this century”.

El Niño could fuel extreme weather and raise temperatures to record highs this year, but how sure can we be that it will return?

Continued global heating could set irreversible course by triggering climate tipping points, but most people unaware

The world seems headed into another El Nino, just 3 years after the last one. Such quick return normally would imply, at most, an El Nino of moderate strength, but we suggest that even a moderately strong El Nino may yield record global temperature already in 2026 and still greater temperature in 2027. The extreme warming will be a result mainly of high climate sensitivity and a recent increase of the net global climate forcing, not the result of an exceptional El Nino, per se. We find that the principal drive for global warming acceleration began in about 2015, which implies that 2°C global warming is likely to be reached in the 2030s, not at midcentury.

With warming set to pass the critical 1.5-degree limit, scientists are warning that the world is on course to trigger tipping points that would lead to cascading consequences — from the melting of ice sheets to the death of the Amazon rainforest — that could not be reversed.

For more than three decades, Brazilian climate scientist Carlos Nobre has warned that deforestation of the Amazon could push this globally important ecosystem past the point of no return. Working first at Brazil’s National Institute for Space Research and more recently at the University of São Paulo, he is a global authority on tropical forests and how they could be restored.

President formally files new plans under Paris agreement and hails ‘boldest climate agenda in American history’. Joe Biden has announced tougher targets on the US’s carbon dioxide emissions for the next decade, in a defiant final gesture intended as a “capstone” on his legacy on the climate. With just weeks to go before Donald Trump enters the White House, the Biden administration is formally filing new plans under the Paris agreement – the global climate treaty from which Trump has vowed to withdraw.

Critical tipping points in the climate system are the flies in the ointment when it comes to accurate prediction of where our planet is headed

The Greenland Ice Sheet covers 1.7 million square kilometers (660,200 square miles) in the Arctic. If it melts entirely, global sea level would rise about 7 meters (23 feet), but scientists aren't sure how quickly the ice sheet could melt. Modeling tipping points, which are critical thresholds where a system behavior irreversibly changes, helps researchers find out when that melt might occur.

Energy return on investment (EROI) is a biophysical and ecological economics concept that is useful to think about how organisms, ecosystems and societies must obtain enough surplus energy returned from energy gathering activities to live, reproduce, and thrive. EROI can help us overcome the false dualism between nature and society. EROI is a useful metric for economics because it is based on immutable physical laws rather than sometimes arbitrary human preferences. It is essential for assessing useful power, energy trade-offs, efficiencies (and inefficiencies), resource depletion trends, resource quality, and surplus potentials of different fuels and technologies that power, or might power, our socio-economic systems. Apparent inconsistencies in the literature can generally be reduced or eliminated by paying careful attention and explicitly stating boundaries and definitions. We argue that proper use of EROI is critical to understand the interconnections among the environment, energy, and socio-economic deve