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engineering
Techniques such as solar radiation management may have unintended consequences, scientists say
During the past decades, the idea of acting to counteract the damage done to the ecosystem by humankind's activities has moved along at least two planning stages.
Terrestrial ecosystems have taken up about 32% of the total anthropogenic CO2 emissions in the past six decades1. Large uncertainties in terrestrial carbon–climate feedbacks, however, make it difficult to predict how the land carbon sink will respond to future climate change2. Interannual variations in the atmospheric CO2 growth rate (CGR) are dominated by land–atmosphere carbon fluxes in the tropics, providing an opportunity to explore land carbon–climate interactions3–6. It is thought that variations in CGR are largely controlled by temperature7–10 but there is also evidence for a tight coupling between water availability and CGR11. Here, we use a record of global atmospheric CO2, terrestrial water storage and precipitation data to investigate changes in the interannual relationship between tropical land climate conditions and CGR under a changing climate. We find that the interannual relationship between tropical water availability and CGR became increasingly negative during 1989–2018 compared to 1960–1989
Flash drought, characterized by unusually rapid drying, can have substantial impact on many socioeconomic sectors, particularly agriculture. However, potential changes to flash drought risk in a warming climate remain unknown. In this study, projected changes in flash drought frequency and cropland risk from flash drought are quantified using global climate model simulations. We find that flash drought occurrence is expected to increase globally among all scenarios, with the sharpest increases seen in scenarios with higher radiative forcing and greater fossil fuel usage. Flash drought risk over cropland is expected to increase globally, with the largest increases projected across North America (change in annual risk from 32% in 2015 to 49% in 2100) and Europe (32% to 53%) in the most extreme emissions scenario. Following low-end and medium scenarios compared to high-end scenarios indicates a notable reduction in annual flash drought risk over cropland. Flash droughts are projected to become more frequent unde
Pie-in-the-sky fantasies of carbon capture and geoengineering are a way for decision-makers to delay taking real action
La start-up Neext Engineering s'est associée à Westinghouse, General Electric et au Centre national de la recherche scientifique (CNRS) pour porter son projet de petite centrale nucléaire destinée à la décarbonation de l'industrie, a-t-on appris mardi auprès des fondateurs.Créée à l'automne dernier à Belfort, Neext Engineering veut mettre au point de petits réacteurs nucléaires modulaires, connus sous le nom de SMR (small modular reactor) et qui équipent par exemple porte-avions et sous-marins nucléaires français.
Mexico announced this Tuesday a set of measures to ban solar geoengineering experiments in the country, after a US startup began releasing sulfur particles into the atmosphere in the northern state of Baja California.
The federal effort could set the stage for more studies into the feasibility, benefits and risks of one of the more controversial means of combating climate change.
More climate scientists say emissions cuts are not enough and we face imminent catastrophe unless deliberately altering the climate. What are the options and challenges? Jem Bendell interviewed Dr Ye Tao who is proposing we use massive amounts of mirrors to reduce harm in the short term.
Later this year, Egyptian engineering firm Arab Contractors is expected to complete the construction of the Julius Nyerere dam on the Rufiji River. Once completed, the $3 billion dam could be Africa’s fourth biggest by power production, producing up to 5920GWH of power annually, enabling Tanzania to close the gap between those with electricity and those who have no access.
This article argues that resource and logistical constraints weighing on low-carbon energy and CO2 capture technologies are likely to pave the way for geo-engineering solutions such as Stratospheric Aerosol Injection (SAI), which demand negligible land, material, and energy inputs. This “climate transition without carbon transition”, though technically feasible, is far from being that simple, raising a whole new set of environmental risks as well as geopolitical, institutional, and ethical issues.
Around the world, dozens of ingenious projects are trying to ‘trick’ the ocean into absorbing more CO2. But critics warn of unforeseen consequences
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The United States and Saudi Arabia have hamstrung global efforts to scrutinise climate geoengineering in order to benefit their fossil fuel industries, according to multiple sources at the United Nations environment assembly, taking place this week in Nairobi.
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Plastics in the marine environment have become a major concern because of their persistence at sea, and adverse consequences to marine life and potentially human health. Implementing mitigation strategies requires an understanding and quantification of marine plastic sources, taking spatial and temporal variability into account. Here we present a global model of plastic inputs from rivers into oceans based on waste management, population density and hydrological information. Our model is calibrated against measurements available in the literature. We estimate that between 1.15 and 2.41 million tonnes of plastic waste currently enters the ocean every year from rivers, with over 74% of emissions occurring between May and October. The top 20 polluting rivers, mostly located in Asia, account for 67% of the global total. The findings of this study provide baseline data for ocean plastic mass balance exercises, and assist in prioritizing future plastic debris monitoring and mitigation strategies. Rivers provide a m