Another campaign featuring pictures of people on rafts or flood-damaged communities wasn't going to cut it. So we created 'Washed Away' - a rain triggered campaign. Real time weather data triggered our messages, along with heartbreaking images of flood-damaged toys, every time it rained.

According to Marketing Week, this was the first ever rain triggered billboard. Live weather data had never been used to disrupt the advertising schedule like this before.

Even our social posts were rain-triggered, and geo-targeted to cities outside London, helping us spread the message further afield.

We identified a renowned humanitarian and environmental photojournalist to capture the images. His work in war-torn and weather-ravaged countries meant that he’d already seen the devastating effects of climate change and flooding.

The heart-wrenching images were the emotional punch of a charity advertising campaign with a difference; one that fused outdoor technology and local data in a brand new way.

In the week before the march, rainfall triggered the ad, disrupting the schedule.

The effect was strikingly simple but there was innovation behind the scenes. The billboard was linked to a nearby rooftop sensor which used electromagnetic pulses to analyse the weather. Real time data from the sensor was analysed by a custom coded algorithm which determined the exact levels of rainfall, every second.

The moment it rained, a version of the ad that intelligently described the real time rainfall (for example, drizzle, light showers, heavy rain...) would play out. All this within a matter of seconds.

Supported by rain-activated Facebook posts geo-targeted to cities beyond London, the campaign fused contextual, real-time data with hard-hitting emotion: The powerful images of children’s toys washed up in Bangladesh, captured by environmental photojournalist Antonio Olmos.

The campaign resulted in the largest ActionAid presence at a public demonstration since Make Poverty History in 2005. We’d moved Londoners not just to share or donate, but to contribute their time. On the back of the campaign, ActionAid spokesperson Himaya Quasem gave the opening speech at the march to more than 50,000 people.

As the world’s leaders converged on Paris for COP21, we gave ActionAid a credible voice in the climate change debate:

Knowledge/consideration:

282 pieces of coverage, including the Daily Mail and interviews on BBC Asian Network and London Live. Rain triggered the advertisement six times during the week, with run time of 2hrs.

Outputs/business results:

* Facebook reach: 30,965

* Twitter impressions: 1,111,922

* Total engagement: 12,835

* Blogs: 1,100 views

* Landing page: 2,563 views

Total reach: 343 million (400,000 target).