I am thinking a lot about the warning issued earlier this week by the Intergovernmental Panel on Climate Change (IPCC) to act NOW on climate change. There is only a short time left to put measures into place avoid the worst effects of climate change. We have already caused a 1 °C temperature rise over pre-industrial levels. It’s still possible to limit the global mean temperature rise to 1.5 °C, but this requires a radical cut in carbon emissions of 45 % over the next 12 years. In other words, this requires a huge change in the way we use transport, heat and light our homes and produce our food.

If we drag our feet on cutting emissions then the mean global temperature rise will reach or exceed 2 °C, dramatically increasing the risk of weather-related disasters, such as floods, droughts and extreme heat. The effects of a 2 °C rise would be devastating. Only 1 % of corals would survive and insects, which are essential for pollinating our food, would lose 50 % of their habitat.

Some people will see this warning as over-dramatic. Others might sense a conspiracy: are the scientists playing a political game?

Are these scientists for real?

I am taking this warning to heart because I was a climate scientist, before giving up work to bring up my children. I’ve worked in three different countries and three different organisations which were involved in monitoring the climate. This work brought me the privilege of meeting many dedicated climate scientists, some of whom contributed to previous IPCC reports.

I’ve sat through seminars and lectures where people have presented model scenarios. They put in the best knowledge about the present climate and carbon emissions and run their models to see what happens in the future. What happens if we stick our head in the sand and do nothing? What happens if we cut emissions by 50 %, 75 %, and so on?

I learnt that what might seem to the layman to be small rises in global mean temperature of a few degrees centigrade can have huge effects. Some areas, such as the Arctic, will experience mean temperature rises of 4 to 5 °C, causing melting of sea ice and rising sea levels. Increased temperature also means more evaporation, which means more rain and greater risk of floods.

As a scientist, I’ve been involved in making careful measurements of atmospheric gases and have seen how they changed over time in response to the changing climate. My work has also gone through a rigorous peer review process. Nothing can get published in a scientific journal without being reviewed and criticised by at least three anonymous reviewers. They will point out any holes in your arguments and there’s no way you can slip in any assertions without providing solid evidence.

Believe me, the IPCC report and the scientific studies it is based on, are not fantasy or wild guesses. They represent our absolute, best estimate of what will happen in the near-future based on accurate current measurements.

Is there still time?

In the 1990’s, when I began working in this field, there was still time. The dire scenarios predicted for the mid 21^st century seemed a long time away, but now they are a lot closer.

What the latest IPCC report is saying is that time is almost running out. There’s no time left to argue. We have to act now.

Hope?

I’ve been feeling really low. In fact, I’ve felt hopeless and overwhelmed. If politicians won’t act, how can my small choices to grow my own potatoes and vegetables or to walk or cycle instead of using a car, make any difference?

And it isn’t enough for a few small nations to act on climate change. This has to be a concerted effort. We must recognise our common humanity and responsibility for the planet. The warning is stark. There’s no part of this planet which won’t be affected by climate change.

Through my daughter’s illness, I have been going through my own test of faith and hope. Recently, someone passed on this quote by the Scottish author, Robert-Louis Stevenson:

To travel hopefully is better than to arrive, and the true success is the labour.

Hope doesn’t know the outcome. Hope doesn’t ignore the difficulties. If it was easy and the way was clear, we wouldn’t need hope.

To save our climate, we must travel hopefully

What about faith?

The Presbyterian group I grew up in was suspicious of movements to protect the environment. They saw these efforts as potentially stabilising the ‘God-given’ status quo. The evangelicals I met at university seemed indifferent to environmental issues. Why make an effort to save the climate if the world was going to be destroyed anyway in Armageddon and God was going to give us a new one?

As I learnt about the threat of climate change on my science course, I wondered why God would give us a new heaven and a new earth, if we haven’t taken good care of this one? He’d be like a parent who buys a new expensive toy for their child after they’ve trashed the first one.

At the same time, I met atheist friends who were passionate about climate and social justice issues. This was a factor, although by no means the only one, in drifting away from religion.

Having come back to Christianity, I was very happy that Pope Francis published Laudato Si, his encyclical on the earth, our common home. This signals a change in the church’s attitude, from seeing us as caretakers rather than exploiters of the planet.

Scottish Catholic organisations, such as SCIAF and Justice and Peace Scotland are campaigning against climate change, because it as a social justice issue. Acting to limit climate change is a matter of justice for people living on the margins: on low lying islands, in dry areas where crops often fail, in areas prone to flooding, as well as for our children and future generations.

It is a huge task. As individuals we are small and weak, but God works through our weakness.

I’ll give the last words to Gordon MacIntyre-Kemp, who writes about the economy in The National, a Scottish newspaper. He points out that action on climate change, requires a whole new way of living and a new economic model:

“Our economic system cannot survive unless the population work hard to buy things they do not need and cannot afford….The existential crisis of our age is that we are killing the planet to consume goods we don’t need and that often make us miserable because we borrowed to buy them.”