>> London was more happy than sad on Friday morning. That's according to live data gathered from geo-located tweets, and shown in this visualization called Pulse. Part of a new exhibition exploring the ways in which global cities are being shaped. There are 400,000 surveillance cameras in greater London, just one aspect of the vast array of technology that shapes the cities we live in today.
I'm David Doyle reporting for Reuters from the Museum of London. Close circuit television is a more old school method of surveillance. But as Amanda Taylor co-founder of Techja the company behind Pulse, says the data we give away creates a picture of a city.>> You can understand where people are, where people are moving.
From a kind of city perspective, this is really interesting because you reveal in effect the invisible city. You understand things about citizens and places that you may be wouldn't before. So when you're looking at designing parts of the city, you can understand who you're designing for.>> The age of apps, smart phones and social media, brings with it questions over what access government and business should have to your data.
>> We believe that data has real potential to do good in the world and improve, and empower citizens. It's vital that citizens know the information that they're giving away, and it's important that when anyone uses data a higher level, for example in city management. That they understand the implications of data privacy and that they work to empower the citizens.
>> Pulse will continuously run for nine months processing an expected 17 million tweets.>> Tweets that also reveal how people react to tragedies, such as the London Bridge terror attack and the Grenfell Tower blaze, in which 80 people died. Taylor says the response seen in the data is invariably messages of solidarity, empathy, resilience and love.
>> I feel so much more positive about humanity, having tracked this data for the past few months. Because it's been a terrible time, and I think certain aspects, if you read the news or you can get a sense that everything's just a disaster. But actually when you look at humans themselves and when you look at how people are responding, ultimately, completely positive.