Friday, 28 February 2014

Natural Capital science at CEH

We're delivering our new Science Strategy (2014-19) through a number of Science Areas and underpinning activities. Find out more about each area as we profile them over the coming weeks in a series of blog posts.

This post focuses on our Natural Capital Science Area, headed by Professor Mike Acreman.

Soil, insect pollination, water, food, nutrient cycling, flood control etc - we rely on goods and services provided by the natural environment. The concept of natural capital as the stock of environmental assets will inform decisions on how we use our natural resources and manage the environment sustainably.

Wetlands, such as this blanket bog on the Isle of Harris, provide essential ecosystem
functions and services, including regulation of water quality, sustainable control and
mitigation of flooding, greenhouse gas reduction, essential habitats for plants and
animals, and cultural and recreational facilities.

CEH carries out a wide range of research into wetlands in the UK and overseas.

CEH has unrivalled and longstanding expertise in the science of the natural environment that underpins natural capital. We'll use surveys, experiments, analysis and modelling to produce detailed knowledge of water, soils, plants, animals and atmosphere provided by the UK environment.

Research objectives in this Science Area include assessing the extent, quality, trends and vulnerability of the UK's natural capital. We also define ecosystem services that flow from the natural and managed environment, quantifying short and long-term trends and natural variations.

We'll also work with other experts in economics, health and sociology, to evaluate the benefits of natural capital to human well-being, how to balance exploitation with protection and where to target management and restoration efforts. For example, we are a partner member of the Natural Capital Initiative.

Long-term monitoring helps us record how natural capital is changing and identify the causes of change. For example, CEH coordinates the UK Environmental Change Network, and operates the UK Butterfly Monitoring Scheme in partnership with Butterfly Conservation and the Joint Nature Conservation Committee.

More details of our Natural Capital Science Area, including a Science Area Summary [PDF], are available on our website.

Additional information

CEH Science Strategy

Tuesday, 25 February 2014

Ecological processes and resilience - science area at CEH

We're delivering our Science Strategy (2014-2019) through a number of Science Areas and underpinning activities. Find out more about each area as we profile them over the coming weeks in a series of blog posts. 

This post focuses on our Ecological Processes & Resilience science area, which is headed by Dr Allan Watt. Understanding of ecological processes, particularly those that affect the resilience of species, is needed to maintain ecosystems and the delivery of ecosystem services.

The benefits that flow from biodiversity and ecosystem services are increasingly under threat from environmental change. Threats include habitat loss and fragmentation, climate change and over-exploitation of natural resources. The threats are exacerbated by pests, diseases, alien invasive species and other drivers of global environmental change.

In our research we combine long-term datasets and use citizen science, models and experimental systems to examine the impacts of single and multiple drivers, including socio-economic drivers, on populations, species and ecosystems.

Other research objectives include assessing strategies to adapt to climate change in forestry, assessing lake restoration techniques, quantifying links between biodiversity and resilience to invasion by pests across a range of ecosystems, and linking time-series data from different trophic levels to assess the degree of synchrony of species interactions.

Long-term monitoring activities that help us in this Science Area include the Isle of May Study,  the UK Butterfly Monitoring Scheme and Loch Leven surveillance.

Find out more about our Ecological Processes & Resilience Science Area, including a Science Area Summary [PDF], on the CEH website.

Additional information

CEH Science Strategy

Lake restoration research at CEH

Staff page of Dr Allan Watt

Monday, 24 February 2014

Understanding Biosphere - Atmosphere Interactions and feedbacks

CEH's new Science Strategy, which was published in January 2014, identifies three interdependent, major societal and environmental challenges: Securing the Value of Nature, Building Resilience to Environmental Hazards, and Managing Environmental Change. We're delivering the strategy through a number of Science Areas and underpinning activities.

Over the next few weeks you can find out more about each Science Area as we profile them in a series of blog posts.

The first Science Area to focus on is Biosphere-Atmosphere Interactions. There are crucial societal and environmental issues relating to air pollutants, greenhouse gases, and global carbon and nitrogen cycles. CEH research aims to understand and quantify interactions between the biosphere and atmosphere based on measurements, experiments and modelling of greenhouse gases, reactive air pollutants, water and energy.

CEH's long-term investigations at Auchencorth Moss, an ombrotrophic peat bog
in Midlothian, demonstrate that these areas remove significant amounts of carbon
from the atmosphere. Photo: Barnaby Smith/CEH.

See more photos of Auchencorth Moss field site on Flickr.

Developing the policy basis for addressing these issues demands the combination of monitoring and modelling of the exchange of gases, aerosols, particulate material, energy and water at land and water surfaces, and effects on local, regional and global climate.

Read more about our Bioenergy crops research in our Energy and the Environment portal.

CEH has studied the impact of bioenergy crop land-use changes
on soil carbon stocks and greenhouse gas emissions.

CEH science quantifies environmental impacts and provides evidence
for policy-makers.

Our Nutrient World, published in February 2013, highlighted how humans have massively altered the natural flows of nitrogen, phosphorus and other nutrients. While this has had huge benefits for world food and energy production, it has caused a web of water and air pollution.

The Review of Transboundary Air Pollution, published in June 2012, found that the chemical climate of the UK has changed dramatically over the last 30 years and continues to change as a consequence of UK and European policies to solve air pollution problems.

Recently published research and commentaries highlight some of our work in Biosphere - Atmosphere Interactions.

Read more about Biosphere-Atmosphere Interactions on the CEH website, including a Science Area Summary [PDF].

Wednesday, 19 February 2014

UK Butterfly monitoring – explaining the schemes and surveys

There’s been lots of coverage today of a new set of data on UK butterfly numbers. You may have seen headlines such as “Farmland butterflies bounce” back and “British farmland butterflies bounce back after 2013 summer, survey finds”.

The reports are based on a new release of data which was collected in 2013 as part of the Wider Countryside Butterfly Survey (WCBS).

The WCBS is run by Butterfly Conservation, the British Trust for Ornithology (BTO) and The Centre for Ecology & Hydrology (CEH).

As today’s press release from Butterfly Conservation states The annual survey (WCBS), running since 2009, counts butterflies in more than 850 randomly selected 1km-squares across England, Wales, Scotland and Northern Ireland to assess the health of butterfly populations across the wider countryside rather than at specially managed hotspots such as nature reserves.” 

Common blue (photo by Ross Newham)

WCBS is part of the United Kingdom Butterfly Monitoring scheme (UKBMS), which has been running since 1976, and has a remit to monitors changes in the abundance of butterflies throughout the United Kingdom since 1976. Regular readers of this blog will already know how UKBMS data contributes to some of the biodiversity indicators which inform UK environmental policy making.

For those confused by the multiple butterfly surveys and schemes operated in the UK the following details may help.

  • Wider Countryside Butterfly Survey, running since 2009, aims to more effectively monitor the changing abundance of widespread butterfly species across the general countryside.
  • United Kingdom Butterfly Monitoring scheme, running since 1976, is very effective at monitoring habitat specialist butterflies and lowland semi-natural habitats.

According to the UKBMS website, in the 37 years the scheme has operated, "Recorders have made around a quarter of a million weekly visits to more than 1,500 separate sites, walking over half a million kilometres and counting over 16.4 million butterflies! 

The UKBMS 2013 results should be out in a few weeks time. The 2012 results were published on 26 March 2013.

All the butterfly surveys, as well as the majority of wildlife recording in the UK, principally rely on the efforts of volunteers so I’ll leave the last word to Kate Risely. Kate co-ordinates the Breeding Bird Survey butterfly surveyors at the BTO. She commented earlier, "These results demonstrate the value of large scale volunteer surveys for monitoring country-wide trends in butterfly numbers. Recording butterflies and birds at the same sites gives us a unique insight into the health of our countryside.”

Barnaby Smith, Media Relations Manager, Centre for Ecology & Hydrology

Update 20 February 2013

Links to CEH news stories about the Wider Countryside Butterfly Survey

2013 results Farmland butterflies thrived in 2013
2012 results Grass-feeding butterflies defy 2012 deluge
2011 results Small Tortoiseshell decline highlighted in new study

Links to CEH news stories about the United Kingdom Butterfly Monitoring scheme

The 2013 results will be published in a few weeks
2012 results Washout 2012 was the worst year for UK butterflies on record
2011 results Record-breaking 2011 Spring helped some of the UK's rarer butterflies
2010 results Rare butterflies show signs of recovery
2009 results Fears grow for some of Britain's rarest butterflies
2008 results UK butterfly numbers fall to new low
2007 results Butterflies at record low after wet summer of 2007

United Kingdom Butterfly Monitoring scheme data and results

Key findings including annual, 10-year and long-term (series) trends for 56 species
Reports and publications
Obtaining data

Thursday, 13 February 2014

Scientists from CEH comment on the ongoing flooding situation in the UK - 13 February 2014

Scientists from the Centre for Ecology & Hydrology have provided the following new comments on the ongoing storms and flooding situation in the UK.

You can read our previous comments (published on the 11 February 2014) here.

Prof Richard Harding,  Centre for Ecology & Hydrology, on the December/January/February floods

"The weather in the last two months has been exceptional. It has been characterised by frequent rain systems tracking across the south of Britain, often associated with high winds. In January the rainfall totals were locally 300% above average and over 200% over a large part of southern England. The result of this relentless rainfall has been that soils and underlying aquifers are now full and the rivers and wetlands have more water flowing through them than has been observed for many decades.
"The repeated passage of storms over England has been caused by a persistent Jet stream to the south of its usual position. This persistence may be linked to the reduction of sea ice in the Arctic or warm sub-tropical sea temperatures. We have observed in the last five decades a rise in temperatures and an increase in the amount of water vapour in the atmosphere – these almost inevitably lead to an intensification of storms and increases in rainfall. Indeed we have observed an increase in the intensity of rainfall in this period. The last two decades have also brought exceptional extremes in our rivers and groundwater– with floods in 2000/01, 2002/3, 2007, 20011/12 and now 2013/14 interspersed with droughts in 2003 and 2011/12. All these trends are entirely consistent with the effects of increasing CO2 in the atmosphere.
"In the short term the saturated nature of the ground means that rivers and low lying areas are very vulnerable to flooding. In the longer term this exceptional weather and extensive floods highlights that we are going to have to adapt to much more variability and extremes in the future."

Mr Nick Reynard, Science Area Lead for Natural Hazards, Centre for Ecology & Hydrology

"After the devastating summer floods of 2007 the Pitt Review carefully analysed all aspects of how this country prepares for and deals with flooding. Post Pitt there have been two key developments in the implementation of flood forecasting science to better predict both the risks and impact of flood events. The first is the development of the Flood Forecasting Centre, which combines meteorological and hydrological expertise to provide forecasts for all natural forms of flooding - river, surface water, tidal/coastal and groundwater. River flow forecasting is underpinned by the Grid 2 Grid model developed by the Centre for Ecology & Hydrology.
The second significant development has been an increased focus on surface water flooding - many of the 55,000 homes affected in 2007 were flooded by a surface water event. Surface water flooding is a key focus of the recently formed Natural Hazards Partnership, which provides information, advice and analysis to government and emergency responders across the UK in the preparation, response and review of natural hazards. and brings together expertise from across the UK's leading public sector agencies and research institutes."

Mr Terry Marsh, Leader of the National Hydrological Monitoring Programme, Centre for Ecology & Hydrology

"The tempestuous weather affecting the UK has continued through the first two weeks of February 2014. It appears likely that winter rainfall totals across much of Southern Britain will be the highest on record (in the NCIC series from 1910). As a result river flows have continued to increase in parts of the country, most notably in the Thames and the Severn basins. In recent days on the Thames river flows are approaching or have exceeded maxima recorded in the last major event (November 1974). The high river flows have led to extensive floodplain inundations aggravated by groundwater flooding in many vulnerable parts of the catchment."

Tuesday, 11 February 2014

Scientists from CEH and BGS comment on the ongoing flooding situation in the UK - 11 February 2014

Scientists from the Centre for Ecology & Hydrology and their NERC colleagues in the British Geological Survey have provided the following comments on the ongoing storms and flooding situation in the UK.

We published further comments on 13 February 2014. Read them here.

Mr Terry Marsh, Leader of the National Hydrological Monitoring Programme, Centre for Ecology & Hydrology

"One of the issues for the public perception to take on board is what we are currently seeing is the Thames exercising its natural sovereignty over its floodplain. This happens occasionally and in a sense it’s good for people to recognise that this happens. Management needs to limit the damage but it would be, I suggest, even worse if we found ourselves in the position where people thought because we’ve not seen this extent of flooding for 40 years that it’s not going to happen. It’s a natural part of the way rainfall patterns translate into river flow patterns."

Dr David Boorman, Science Area Lead for Water Resources, Centre for Ecology & Hydrology

"A key question in any unusual hydrological situation, such as a drought or a period of wet weather as we are experiencing now, is how long will it continue? We are working with a number of partners to provide a long-range hydrological forecast for the UK. Forecasts of this type are already produced on an operational basis in a number of countries including the USA and Australia.

“The project involves bringing together information on the current weather, soil moisture, river flows and groundwater levels from across the UK, and using a number of methods of exploring possible future hydrological conditions, for example, using numerical models of river flows and groundwater models driven by long-range weather outlooks."

Mr Nick Reynard, Science Area Lead for Natural Hazards, Centre for Ecology & Hydrology

"The cluster of drought and flood events through the early years of the 21st century and the recent runoff and recharge patterns, are near to the extreme range of historical variability as we currently understand it , and therefore also raise the question that they may reflect anthropogenic climate change. It is important to note, however that how river flows respond to extreme rainfall varies greatly because of geology, soils, land use etc, meaning that it is difficult to detect signals of climate change in observed events, and to generalise the impacts of climate change for future flooding. Tidal flood risk is increasing as sea levels rise but the outlook is more complex in relation to fluvial flooding."

Prof Alan Jenkins, Director of Water and Pollution Science, Centre for Ecology & Hydrology

"The long duration of the current flooding episode and its wide spatial extent make it an exceptional event. Relentless storm events over many weeks have combined to produce widespread flooding at a scale rarely seen in the UK. Over 5000 homes have flooded and transport infrastructure has been disrupted across the UK.

“The key to mitigating the impact of any flood is understanding that every catchment works in a different way. For example the current flood situation on the Somerset Levels is the result of a different range of processes to those currently affecting the lower reaches of the River Thames. The operational agencies are doing a sterling job on the ground and it’s important to recognise that hundreds of thousands of homes have been protected by the UK’s flood defence infrastructure.

“Many potential solutions have been talked about over the last few weeks as ways of minimising flood risk. This is a complex issue and over the next few months it is important that experts from the key agencies and research institutes sit down and carefully analyse whether there are lessons to be learnt from the current flood episode."

Dr Chris Huntingford, Climate Modeller, Centre for Ecology & Hydrology

"In terms of climate change, there is a desperate need to move away from the almost Punch-and-Judy debate of either every extreme is due to climate change, or the contrast of everything is simply natural variability. Desperately needed is the on-going calculation of whether higher atmospheric concentrations of carbon dioxide are changing the chances of rainfall events, as recently witnessed, occurring.

To work this out, weather forecast models that analyse the atmosphere in such fine detail as to model storm tracks, need to be operated for different levels of modelled carbon dioxide. Running these for hundreds of modelled years for alternative carbon dioxide concentrations, so as to build up statistical profiles of rainfall patterns, presents one of the biggest computational challenges ever tackled."

Mr Simon Parry, Hydrologist, Centre for Ecology & Hydrology

"Each one of these individual events has not been particularly outstanding, they've been broadly along the lines of what we would expect for a typical winter storm in the UK. What's been notable about it, and different from what we've seen in the past, is the persistence. The combination of high tides, strong winds and a succession of rain-bearing low pressure systems has led to widespread and sustained high flow conditions over a two month timeframe."

Mr Andrew McKenzie, Groundwater Information Manager, British Geological Survey

"In early December 2013 groundwater levels over much of the UK were normal for the time of year. The extreme rainfall in the southern part of England over the New Year and into early January had a dramatic impact on levels in the faster responding aquifers and spectacular rises occurred in groundwater levels in some aquifers. For example, groundwater levels in the Chalk at Tilshead on Salisbury Plain rose by about 20 metres in just two weeks. These rapid rises triggered some localised groundwater flooding, mainly in the upper parts of Chalk catchments. If rainfall had eased at that point the empty storage in the lower catchment might have been able to absorb the inflows. However, as rainfall has continued to fall the lower parts of many catchments have been saturated, and prolonged high river levels will have contributed to exceptional recharge.

“At the beginning of February record monthly groundwater levels were measured across many aquifers, and as levels in February are naturally high, these records are often all time records for the sites concerned. Record levels were established in the Chalk of Wessex, the North Downs and Hampshire. The wet weather also reversed a declining trend in some of the North West Permo-Triassic aquifers.

“Consequently, emergence of groundwater has been observed at many localities across southern England where groundwater flooding has been previously recorded. The high water levels on the interfluves (the upper parts of groundwater catchments) will gradually feed into the lower parts of the catchments, over a period of weeks to months, so groundwater flooding is expected to persist."

Additional information

Journalists can contact the CEH Press Office or the BGS Press Office for further context on the UK's hydrological situation. 

Further information from CEH can be found in the following blog posts:

Record breakers? Climate change, statistics and the recent UK floods - 9 February 2014

Rainfall, UK floods and the potential impacts of climate change? - 6 January 2014

CEH worked with the Met Office on a report on the recent storms and floods in the UK.

Sunday, 9 February 2014

Record breakers? Climate change, statistics and the recent UK floods

This morning the Met Office and the Centre for Ecology & Hydrology released a report on the recent storms and floods in the UK.

You can read the full report here, and a short summary of the hydrological analysis on our website here

The report documents the recent record-breaking weather and flooding episode, and discusses whether climate change contributed to the severity of the weather and its impacts. Climatology, meteorology and hydrology are covered in the report. 

In this blog post we highlight some of the hydrological conclusions that came from analysis of the long-term datasets held at CEH and our long history of research into floods.

With regard to the record-breaking nature of the flooding the report makes the following points:

  • The full gamut of flood manifestations – tidal, pluvial (flash), fluvial and groundwater – has been experienced over the last eight weeks.
  • The exceptional run of severe winter storms over December 2013 and January 2014 carried with them large amounts of rain which has led to very serious flooding across southern England. 
  • Estimated outflows (river flows) from Great Britain remained close to the highest ever recorded during late December and, subsequently, throughout most of January across large parts of England and Wales.
  • In a series from 1883, flows on the River Thames at Kingston (close to the tidal limit) remained above 275 m3 s-1 for longer than in any previous flood episode, and continue to exceed this threshold into early February. 
  • A preliminary analysis suggest that outflows aggregated over six weeks were the greatest since the 1947 floods – the most extensive in England & Wales during the 20th century.
  • In December and January, a few rivers (including the Mole, Wey and Medway, which, on the basis of preliminary data, recorded their highest flows since the extreme floods of September 1968) registered outstanding maximum flows. 
  • Generally, however, the peak flows registered during the recent flooding were not extreme. On the Thames the highest flow in 2014 has been exceeded during 14 earlier floods (most prior to 1950). 
  • The floodplain inundations across the UK caused major disruption to transport, agriculture and restricted sporting and recreational activities, and resulted in severe difficulties for some low-lying hamlets (most notably in the Somerset Levels). However, given the overall volume of runoff, the amount of property flooding at the national scale was relatively modest; a tribute to the general effectiveness of flood defences.

Figure 1: Combined flows (m3 s-1; black) for the Thames, Severn, Trent, Yorkshire Ouse and Usk in 2013 and January 2014, plotted against period of record (1969-2013) daily maximum flows (blue), daily minimum flows (pink) and daily mean flows (grey)

With regard to whether climate change has been a contributing factor to the current flooding the report states:

  • The cluster of drought and flood events through the early years of the 21st century and the recent runoff and recharge patterns, are near to the extreme range of historical variability, and therefore also raise the question that they may reflect anthropogenic climate change. It is important to note, however, that differing flood types may be expected to respond differently to increasing temperatures. Tidal flood risk is increasing as sea levels rise but the outlook is more complex in relation to fluvial flooding.
  • Published studies have observed increased river flows in the winter half-year and a tendency for higher flows to occur more frequently, and this has been reinforced in recent years. Importantly, however, such a trend may not be accompanied by any increase in magnitude of major flood events. In the UK, no positive trend in water-year maxima was found in the 130-year series for the Thames.
  • Enhanced groundwater flood risk may be expected if average winter rainfall in the UK increases. Flash flooding, which can be exacerbated by land management and land use practices (particularly the extension of impermeable areas), may also increase if the recent intensification in rainfall translates into an enduring trend. 
Much more detail can be found in the full report. More information about the report's conclusions is available on the Met Office website here.

Journalists can call our Press Office if more information is needed on the hydrological conclusions.

Barnaby Smith, CEH Media Relations Manager

Further links

Jamie Hannaford from the Centre for Ecology & Hydrology contributed a chapter to the Living with Environmental Change climate change report card for water entitled, "Observed long-term changes in UK river flow patterns: a review"

An interim update on the UK's hydrological situation - issued by CEH on 6 January 2014

Rainfall, UK floods and the potential impacts of climate change? - blog from 6 January 2014

NB: the Met Office updated the report on 11 February to give a more detailed assessment of sea level rise

Thursday, 6 February 2014

How exposed are the world’s rivers to pollutant chemicals discharged from domestic sources?

CEH scientists Andrew Johnson, Virginie Keller and Richard Williams blog about their new paper examining pollution in the world’s rivers.

All around the world we use more and more chemicals in toothpaste, drugs, shampoo, hormones for cancer treatment and as a means of contraception. All these chemicals go "down-the-drain" and a proportion escape from sewage treatment plants before entering rivers and potentially affecting wildlife. A good example is the issue of sex hormones discharged by the human population resulting in male fish displaying female characteristics (e.g. egg proteins in their blood, egg sites in their testes), which caused alarm around the world.

One way of finding out the scale of national exposure to such chemicals is to get chemists to test for every chemical in every river in their country. Such monitoring campaigns are extremely challenging and very costly to carry out. Even in countries such as the UK, which has a small geographical area and leads the world in environmental monitoring, the level of effort required is difficult to sustain. For developing nations the expense of such monitoring campaigns means such information and knowledge is beyond reach.

Our new study, recently published as an open access paper in the journal Environmental Toxicology and Chemistry, used a geographic-based model which compares population with river flow to assess the available natural dilution for the human wastes that contain chemicals. The less dilution available within a nation, the higher the exposure levels to these chemicals will be.

As we all know rainfall patterns can vary dramatically throughout the year, and from year to year. The model used long-term annual and monthly averages of river flow (based on up to 60 years of measured rainfall) to generate a range of dilution factors.

Many nations have poorly populated and densely populated regions. Thus, for each nation, a variety of dilution factors were examined (expressed as a range of percentiles). The spatial variability of the dilution factors can vary considerably depending on the percentiles – defining low to high flows – and types of flow considered (annual or monthly).

Predicted values of national annual median (50%ile) dilution factor

The results are interesting. In Europe, the UK median dilution factor of 37 puts it in the upper third of nations exposed to domestic chemicals. However, the 25%ile results – a measure of low flow dilution – give the UK a dilution factor of only 6, making it the most exposed country. This is a consequence of our relatively dry summers and high population densities in the South and Midlands. By way of contrast the French median dilution factor is 76 and 25%ile dilution factor is 47. This tells us that French fish have a lot less to worry about than British fish!

The paper is open access so readers can look up their exposure to chemicals by examining the tables we’ve created. We hope that environmentalists and regulators from countries across the world, as well as the general public, are able to use the results, to better address this important issue.

Andrew Johnson, Virginie Keller and Richard Williams

Additional information

The full paper reference is:

Keller V.D.J., Williams, R.J., Lofthouse, C., Johnson, A.C. (2014). Worldwide estimation of river concentrations of any chemical originating from sewage-treatment plants using dilution factors.
Environmental Toxicology and Chemistry, 33, 447-452. doi: 10.1002/etc.2441

Staff page of Professor Andrew Johnson

Staff page of Richard Williams