THE Intergovernmental Panel on Climate Change (IPCC) will present its latest report next week on the impact that climate change is having on the planet, and what is expected to happen in the future. For Christians, now in the middle of Lent, it comes as a timely reminder - both to think about our brothers and sisters around the world who suffer because of climate change, and to reflect on what part the Church can play.

"For us, climate change is a life or death issue," said the General Secretary of the Pacific Conference of Churches (PCC), some years ago. Communities in the Pacific islands have since been resettled because of the rise of sea level and the salinisation of fresh water. This is the case, among others, with the Carteret Islands in Papua New Guinea, whose inhabitants have been moved to Bougainville, and coastal villages in Fiji, which have moved uphill.

It is not strange, then, that at last year's PCC General Assembly in the Solomon Islands, church leaders backed the continuation of research into climate-induced resettlement, focusing on human rights, as one of the its priorities for the next five years.

RESETTLEMENT is one of the effects of climate change that will be further analysed in the new IPCC report. Its first part of the report, published last year, stated that the scientific community had increased its conviction that climate change is being driven by humans to a near-certainty of 95 per cent (Comment, 27 September; News, 4 October).

The latest report will present examples to show how climate change is affecting different regions. In an early draft, for example, a section on Mali states that nearly six million people there may experience under-nutrition because of changes in climate, livelihood, and demography: somewhere between three-quarters to one million of this number will be children under five. Also, severe child stunting (which leads to a higher mortality risk) is projected to increase by at least 31 per cent across sub-Saharan Africa by 2050, because of climate change.

Although climate change is a global phenomenon, it is not affecting all countries in the same way. Some communities and nations are more vulnerable than others. Low-lying islands, arid parts of Africa and Asia, and particular communities of indigenous people, among others, are especially at risk.

THE ecological crisis has challenged theology, and pushed for a renewed understanding of creation, where the human being should be seen not so much as the master, but as a creature among others, with a special responsibility: to take care of the garden of Eden, as set out inthe second creation story (Genesis 2.15).

A theology of climate change has also emphasised that God is not only transcendent, but present in creation through the Spirit. Furthermore, given the human-induced character of climate change, human behaviour is critical to reverse the trend, and is thus the responsibility of human beings.

From such an ethical perspective, the idea of climate justice is increasingly at the core of ecumenical campaigning. For Christians, God is a God of justice, and asks his people to act justly in taking care of the orphan, the widow, the stranger (Deuteronomy 10.18, Isaiah 1.17). Among the modern-day equivalents of these are the victims of climate change. It is a an issue of justice because those who suffer now, and will suffer the most in future, are those who have contributed least to its causes.

THIS is not only a matter of theology, advocacy, or ethics. Churches are making it a part of everyday Christian living, or of particular seasons, such as Lent. This is a time for Christians to reflect and to rediscover the meaning of praying, sharing, and fasting.

This Lent, for instance, the Anglican Communion Environmental Network is proposing a carbon fast, and suggesting concrete actions each day. The Ecumenical Advocacy Alliance is calling for a "Fast for Life", and encouraging people to join the "zero-waste daily challenge", as a way of illustrating the links between food waste and climate change.

In Switzerland, Christian development agencies are focusing on intergenerational justice for their Lent campaign, linking environment and climate with future generations. Taking a longer-term perspective, the youth wing of the Lutheran World Federation has joined other organisations in a call to fast on the first of each month and to urge governments to be more ambitious in climate negotiations.

Lent calls for conversion, a changing of mind and attitudes, and a change of paradigm. As the World Council of Churches' statement to the UN climate summit in Doha in 2012 put it: "A change in paradigm appears as mandatory in the prevailing economic strategy of promoting endless growth and a seemingly insatiable level of consumption among the high-consuming sectors of our societies."

Climate change is affecting different countries and people in different ways, but our Christian faith calls us to be responsible for our actions - those everyday actions which are contributing to carbon emissions, waste of water, food, and energy. May this Lent be an opportunity for us to convert to a more ecological and just way of life.

Dr Guillermo Kerber, from Uruguay, co-ordinates the work on Care for Creation and Climate Justice at the World Council of Churches, based in Geneva.