IT’S difficult to know what would persuade Donald Trump to believe that humans are responsible for the way the climate is changing. He maintains that the record number, the extent and the severity of the fires that have recently ravaged California are simply the result of poor forest management.

However the locals know differently and point out that the cost of fighting the fires has tripled in the last five years and was certainly well over two billion dollars before the end of last year.

Indeed the thousand plus fire fighters, hundreds of large fire engines and a handful of specialist aircraft are not only an enormous expense but their use over months produces a remarkable amount of its own CO2, and this adds, in some measure, to the warming of the local climate.

While it’s sensible to acknowledge that the increase in population, the building of houses in marginal rainfall areas, and the impact of many of the local lifestyles makes forest burning more likely the overall driving force is what’s happening to the local climate. It’s becoming warmer and drier.

The recent drought in California, from late 2011 until 2017, was the longest, driest and hottest on record. While smaller droughts have been frequent in the past it’s now suggested that at least one quarter of the state is generally without rainfall for long periods, and the area covered is increasing annually with the persistence of the inland Santa Anna winds.

California’s struggle with wild fires since 2009, just the last 10 years, has cost at least five billion dollars and the area effected is now almost state wide, from north to south and becoming more intense by the year.

While climate change will certainly involve a couple of degrees of extra warming in due course, it’s the change to the current rainfall pattern, and the reduction in volume that will cause the initial problems.

California produces far more food than the other states, including dairy products, greenhouse and nursery crops, fruits and nuts. It needs water, not droughts and wild fires.