I am a great fan of the writing of George Monbiot, the environmental campaigner, but the Guardian headline on his column made me wince. “Warning: your festive meal could be more damaging than a long haul flight”.

That’s a prime example of the Christmas catastrophism that afflicts sections of the press at this time of year. It is, of course, important that journalists don't go gooey eyed just because it is Christmas and lose critical faculties.

But nor should we ignore the extent to which humanity is succeeding in addressing a lot of intractable problems. Society will only change if people believe they are capable of change; so we need to recognise and celebrate achievements.

For example, the most important environmental story in the UK this week, surely, is not the carbon gasses emitted by Christmas dinner but that half of Scotland's electricity is generated by renewable energy. This country is ahead of schedule to deliver 100 per cent clean electricity by 2020. Of course, it may not get there, and other climate targets have been missed, but this is a very important development; as is the commercial availability of local electricity storage like the Tesla Powerwall home battery. It sounds boring, doesn't it? It is just a big battery. But local storage means that, if you have a windmill on a remote island, you can hold enough power to run an entire household without being connected to an electricity grid.

Similarly, in hot countries, cheap solar panels with batteries will soon allow people to shake off their dependency on fossil fuels. In Sierra Leone, which I visited this year, most households still cook on wood stoves. This is expensive, dirty and hugely damaging to the environment. Cheap solar power could transform sub-Saharan Africa as promptly as the spread of mobile telephony.

Sierra Leone is the third poorest country in the world but nearly everyone has a mobile phone and most are connected to the internet. The signal is better than in Scotland. According to the UN seven billion people in developing countries have mobiles and nearly half have access to the internet.

This is the greatest and fastest communications revolution in history. Social media is allowing people in remote areas of Africa to have bank accounts, start businesses, get jobs, organise political movements and spread health education.

One of the biggest positive news stories of 2015 was that Sierra Leone became Ebola free in November (partly with the help of mobiles that helped track its spread). But how many of us were aware that, this year, the whole of the continent of Africa has also been free of polio for more than one year? India is also on course to be polio free.

Of course, poverty kills more people than epidemics. But the good news is that the UN's Millennium Development Goal of halving absolute poverty at 1990 levels by 2015 has been far surpassed. Only 14 per cent of the world's population live on less than $1.25 a day.

Of course, relative poverty hasn't been eradicated by any means and is arguably worsening as the inequality gap widens between rich and poor; but credit where it is due. Child mortality is also in decline with the number of children dying before the age of five more than halved in the past decade.

The scandal is that it hasn't been eradicated when it clearly could be. HIV is being tackled but we may have missed the chance to eradicate malaria and tuberculosis is on the rise even in the West. But this is more about politics than medicine. The means are on hand to end the most intractable health problems.

We generally hear negative stories about health, especially in Scotland where it’s assumed by every stand-up comedian that we all drink and eat ourselves to death, shunning exercise and succumbing to heart disease. But according to government statistics, since the smoking ban in 2005, the death rate from heart disease in Scotland has fallen by 43 per cent.

Just reflect on that astonishing statistic for a moment. Mortality in Scotland's number-one health problem has almost halved in a decade. The figures are all available online from the Scottish Government's Information Services Division (ISD). And they are not SNP propaganda.

The decline in heart disease and strokes may not be unconnected to an under-reported change in Scottish lifestyles. According to the World Health Organisation, more than 60 per cent of Scots undertake more than 150 minutes of meaningful exercise every week, a higher rate than in England.

One of the best news stories for me in 2015 was the St Ninian's Mile. The Stirling primary school was criticised initially by some parents for forcing children to run a mile a day in all weathers. But it then it emerged that, not only did children actually enjoy it, but also that obesity reduced markedly and concentration improved.

The headteacher, Elaine Wylie, received the 2015 Pride of Britain Teacher of the Year award for this initiative, which is being taken up by schools across the UK. Yet the St Ninian's Mile is so damned simple you wonder why no one thought of it before.

Simple health education saves more lives than the fancy medical procedures we read about. Drug and alcohol abuse among young people continued to fall in 2015, as did teenage pregnancies. Scotland used to have the highest proportion of gym-slip mums in Europe, but thanks to simple sex education, teenage pregnancies have fallen by 35 per cent since 2007 alone according to the ISD.

Many social problems are very hard to deal with, such as economic inequality, mental health, climate change but a lot require really quite simple changes to make a very big difference. All categories of recorded crime continued to fall in 2015, apart from sex offences and domestic violence that had not been reported in the past.

Criminologists are puzzled. Crime normally increases after economic downturns like the recession of 2008-12. Indeed in 2009, the then shadow home secretary Chris Grayling, forecast a “credit crunch crime wave”. But the decline in reported crime in Scotland continues to fall year on year and has done for nearly a decade.

This is partly because of better security, which has reduce car theft and burglary. Some crime is thought to have migrated to the internet. Then there is the fall in hard-drug use, which fuelled much criminal behaviour. But researchers like Professor Mike Hough of Birkbeck also point to less quantifiable changes in social attitudes. He believes we are becoming a more civil and humane society.

Forms of aggressive behaviour such as domestic violence are no longer tolerated; nor are street fighting, theft and vandalism. People are less narrowly acquisitive and more tolerant. “You're no Muslim, bruv” was the viral saying of the year, uttered by one of the witnesses to the tube station assault.

Okay;this sounds like Pollyanna criminology. And maybe it is. But there were only 59 homicides in Scotland last year, the lowest in recorded history. Something is going right. Happy Christmas.