Outdoor spaces are reasonably safe
The debate for whether it is safer to be outside or indoors might have been concluded with new studies coming from China showing that of the sample group of 7324 cases of COVID-19 that were identified through contract tracing only showed 2 cases that were infections outdoors.
Contact tracing has been a huge point of contention in recent debates as it requires some level of snooping on personal privacy. Calls for the decentralised models and quasi-anonymity have been rejected by the likes of the UK government in favour of centralised alternatives. Draconian stripping of individual civil liberty resonates strongly in the west, and therefore has some cultural barriers to overcome in addition to technical deployment.
While there is always some level of statistical anomaly and/or sample bias, the study conducted in China does show that questions of freedom aside, contact tracing is a powerful tool for analysing how the virus spreads. Research has shown that the minimum viral load to confer transmission is off the cuff, about 1000 drops of aerosolized droplets.
From the study, we can conclude that the risk to infection is drastically lower in outdoor spaces as the wind quickly disperses the particles very quickly, effectively diluting the viral load potential of the virus in the air. But in addition to this, the UV exposure as the weather begins to warm up can aid with killing the virus on surfaces exposed to the sun.
This is not a call to choose to live outside, nor is it a call to congregate in outdoor spaces. People can still transmit the virus through close contact, including touching, shouting, singing or heavily breathing near other people.
This sadly means that it is still unsafe to host festivals a la Coachella which could become mass spreading events due to the extreme close proximity of people in the audience.
Maybe next year!
[Source]
https://www.medrxiv.org/content/10.1101/2020.04.04.20053058v1.full.pdf