mobility

Private flights are used by approximately 0.003 % of the world's population, but the CO₂ emissions they released in 2023 were equivalent to 1.8 % of those of all commercial aviation. These are the conclusions of a study published in the journal Communications Earth & Environment, which estimates that emissions from private flights increased by 46 % between 2019 and 2023. Almost half of them covered a distance of less than 500 kilometers.

A new web-based tool analyzes major cities like Tokyo, Paris, Atlanta or Barcelona to see how close they are to the 15-minute city concept, where residents take less than those minutes to access essential services by foot, bike, or public transport. According to the study, published in Nature Cities, few cities fit this concept. The tool, which is freely accessible and uses data from 10,000 cities sourced from the open-source packages GeoPandas and OpenStreetMap, could be useful for developing action plans and estimating how viable it is to transform certain cities to follow this model.

Analysis of 1,500 climate policies implemented in 41 countries over the last two decades - between 1998 and 2022 - shows that a small proportion - 63 of them - achieved a significant reduction in carbon dioxide emissions. The study, published in Science, indicates that a significant decrease in these emissions was recorded in the transport sector in Spain. According to the authors, the combination of several policy instruments is often more effective than the use of single measures.

According to a large long-term study published in BMJ Public Health, people who cycle or walk to work or school have a lower risk of mental and physical illness. Cyclists benefit the most, with a 47% lower risk of death from any cause, a 24% lower risk of hospital admission for cardiovascular disease, a 51% lower risk of dying from cancer and a 20% lower risk of being prescribed drugs for mental health problems.

A neuroprosthetic interface allows a bionic leg to respond to the nervous system of amputees to make walking faster and more natural, says a study published in Nature Medicine. The clinical trial involved 14 people with below-knee amputations: seven with a surgically attached bionic leg compared to seven without the interface.

A study has compared data from 2,100 accidents involving autonomous vehicles and just over 35,000 accidents involving human-driven vehicles between 2016 and 2022, mainly in California (US). Their findings are that autonomous vehicles are safer in many driving situations, but suffer more accidents in situations such as turning times or during dawn and dusk. The results are published in the journal Nature Communications.  

Combining two types of cameras could enable autonomous vehicles to detect objects accurately and efficiently, say researchers in Switzerland in a study published in Nature. Autonomous vehicles need visual systems capable of detecting fast-moving objects without sacrificing image quality. The system described combines a colour camera with a reduced frame rate - to lower the bandwidth needed to process images - and an event camera, which detects fast movements - such as pedestrians or vehicles - and compensates for the higher latency of the colour camera.  

According to a study on the number of pedestrian accidents in Great Britain between 2013 and 2017, published in the Journal of Epidemiology & Community Health, the risk of pedestrian crashes was twice as high for electric and hybrid vehicles as for petrol and diesel vehicles.  

A study published in the journal Communications Earth & Environment (from Nature Research) estimates that a reduction of 686 million tonnes of carbon emissions could be achieved each year if the world followed a cycling pattern similar to that of the Netherlands (2.6 kilometres per day). This is about 20 % of the carbon emissions produced by the global passenger car fleet in 2015.