Climate change and resilience

The UK is officially warmer, sunnier, wetter. Sounds ideal for agriculture, but sadly it is the way in which this warmer, wetter and sunnier will be delivered that generates the problem. Rather than generally being a bit warmer, a bit wetter and a bit sunnier, nicely spread over the year, delivery will frequently be via some rather more extreme weather events. I’m sure there are producers in the South East who consider, after a run of hot dry summers, that this season’s weather represents a return to normality (whatever that is). Sadly, when one considers weather events around the rest of the UK and globally, I suspect that what we are seeing is simply a blip in the transition towards increasingly hot and dry summers.

A Met Office study report is predicting that we will, within the next decade, be experiencing in some parts of the UK prolonged spells of summer temperatures in excess of 40°C. The prolonged spells of temperatures in excess of 30°C that we have experienced over the past few years have presented significant challenges to both people and livestock (cattle more so than sheep); temperatures of 40°C and above are a completely different proposition and represent significantly greater challenges.

There are many out there who still seek to deny climate change, but the increasing number and severity of extreme weather events would seem to be a strong indication to the contrary. Evidence from the UK alone would indicate this to be the case; we may have had a relatively wet and warm spring and early summer in the South East, but in some parts of the North of England and Scotland the reverse has been the case, with an uncharacteristically dry spring. Just last week (WC 19 July) record temperatures were recorded in Northern Ireland and this week (25 July) parts of London suffered flooding as a result of more than 50mm (close to two inches) of rainfall in a single storm.

Looking further afield supports this view: record floods in Germany, Belgium, the Netherlands and Italy; temperature records smashed in NW USA and Canada (records broken by almost 5°C); flooding in California; above average winter temperatures and severe flooding in May, June and July in parts of New Zealand; record summer temperatures in Siberia and the Arctic; the list goes on.

As an industry we need to recognise the contribution that agriculture has made towards greenhouse gasses associated with climate change, nitrous oxide and methane in particular. The precise level of that contribution is highly debatable and the latter has been largely overstated by those with their own agenda to pursue.

We are, as an industry, a relatively soft target, although we do have the benefit of a growing desire from the general public to understand some of our problems, and rather than focusing on where blame lies we should be looking forward and exploring opportunities to enable us to make contributions to solving the problem.

Firstly, we need to dispel the myth that we don’t need ruminant livestock as part of our agricultural systems; the increase in external pressure to limit the range and quantities of artificial chemicals employed within the wider agricultural sector has in reality enhanced the role of grazing (ruminant) livestock within a balanced agri-ecosystem. We must not, however, fall into the trap of complacency. Sheep producers still have a function to fulfill as producers of quality sheep meat and as contributors to both the reduction of greenhouse gas emissions and the sequestration of carbon. Moving forward, sheep producers need to recognise the need to build into their production systems resilience to the seemingly unrelated areas of social, environmental, financial and climate challenges.

Developing resilience is important to individual sheep enterprises, the sheep sector as a whole and to the climate change debate. The level of resilience to external challenges of whatever complexion does tend to have an inverse relationship to both specialisation and intensification; closely integrated mixed farming systems in general having a greater inherent level of resilience. Some may argue that they are possibly the least financially resilient. This may be partially true in the short term, but longer term this argument is not so persuasive.

The level of resilience that may be developed within a system is largely a factor of mitigation and adaptability. There is little that we can do, in the short term, to mitigate climate changes, but there is a lot that we are able to contribute to the long term situation.

There are, however, steps that we can take to mitigate some of the impacts, ensuring that sheep always have access to adequate fresh water or shade being obvious examples. This may include some strategic tree planting, providing longer term benefits to stock plus some environmental gain. Rams in particular benefit from shade. Prolonged hot weather can have a significant and detrimental effect on sperm production, and as spermatogenesis is a process that extends over seven weeks or so, it is not yesterday’s weather but what was happening a couple of months ago that will have an impact when they go to work.

There is also some considerable scope for mitigation when considering the availability of adequate supplies of grass and forages. Managing grass and forages in a way that helps build soil organic matter has the dual function of building greater resilience into the system, since organic matter retains moisture, and buffering some of the impacts of dry weather. It also locks up carbon in the soil.

Incorporating a greater range of forage crops to include deeper-rooted types and varieties may also have a significant impact, providing opportunities for extending the grazing season (careful selection can provide for an earlier bite, fill some of the summer gap and provide more forages into the autumn) and reducing the reliance on concentrates (with associated cost saving and reduction of methane emissions). The wider use of forages also has the benefits of improved soil health and enhancing both the image and public perception of sheep production. More considered use of grass and forages also has benefits beyond the obvious impact of a more effective use of a valuable resource; longer rotation paddocks, for example, can help to improve soil health and organic matter.

There is a host of areas in which sheep producers may, with a bit of creative thought, devise strategies to help mitigate some of the impact of the changing climate. In addition, greater and more effective use of forages will help reduce costs of production, a key feature in building financial resilience at a time of reducing income.
In terms of adaptability, one of the other key elements in building resilience, I suspect that it is producers that will find this the most challenging and not their sheep. Sheep are remarkably adaptable creatures, a key feature in their incredible success as farmed livestock for thousands of years. Somewhere in the genetic make up of our sheep are the genes for heat tolerance, genes inherited from their wild ancestors in the hot and arid regions of the Middle East and Central Asia. Some breeds no doubt have the capacity to adapt rather more readily than others and we may even, if we see summer temperatures rising to 40°C plus, need to consider some adjustments to the breeds we keep; either different breeds or by outsourcing genetic material for heat tolerance.

Very young lambs are quite vulnerable in hot weather, becoming hyperthermic just as readily as we now worry about them becoming hypothermic. We may need to adjust lambing times to avoid exposing young lambs to the hottest of weather, but what warmer, wetter and sunnier will not do is alter the seasonality and day length of the UK, and it is the latter which controls the seasonality of breeding for most of our temperate sheep breeds. Non-seasonal breeding may become more important, particularly if we have milder winters, both from the point of view of the impact of high temperatures on lambs and the availability of grass and other forages in the hottest of months.

We have recently had a foretaste of the potential impact of climate change. At this point, all we can say with any degree of certainty is that things have changed and will continue to change; the speed and magnitude of that change are speculative. There is the potential for significant and dramatic shifts in weather events and weather patterns; to this end we are moving into relatively unknown territory.

The UK lowland livestock sector, including sheep is, as a result of the removal of the support measures, one of the most vulnerable, but in terms of developing resilience to climate change it is probably one of the best placed; we have greater flexibility and more opportunities to adapt than sheep producers in some of the harsher parts of the country where the production environment dictates and constrains production systems.