The term big data can be understood as being very large amounts of information which when if analysed can lead to interesting insights and improve the ability to predict future outcomes.
Big data concepts are also used in weather forecasting. Data from a hugh range of sources is analysed and compared with patterns from historical data to predict the weather in several days time.
Climate change models are based on big data. These models can be calibrated by weather events. An example would be predictions of wild fires in western USA.
As the amount of climate data proliferates, climate change models that incorporate this data improve. Just as the weather in three days time can be predicted now with a much higher degree of confidence than it could be 20 years ago, so the confidence in climate change models is also improving.
The Intergovernmental Panel on Climate Change (IPCC) will soon be publishing its fifth assessment report on climate change. The report is based on a review of scientific papers published on climate change. Its likely that many of these papers have used climate models in developing their conclusions. Its last assessment report was published in 2007, so it can be reasonably expected that there can be greater confidence in the projections of the upcoming fifth report.
Our ability to predict the likely future impacts of climate changes is improving, as a result of climate change models that are regularly refreshed with the growing amount of climate data.