Thursday, 13 September 2012

When climate models get it wrong

Guest post by Dr Chris Taylor, Meteorologist, NERC Centre for Ecology & Hydrology

Our recent paper on how rainfall processes are represented in climate models (‘Afternoon rain more likely over drier soils’ published online in Nature this week) led to some interesting headlines around the globe including "Shock. Climate models are too alarmist" (Andrew Bolt’s column in the Melbourne Herald Sun). This is not exactly how I’d express the meaning of the paper!

A key result of our work is that the current models are getting the relationship between rainfall and local soil moisture incorrect, and therefore can end up in a vicious circle of drying soil and reduced rainfall. Representing the processes by which clouds and rain develop within computer models in order to make climate projections over the entire globe for decades hence is tremendously difficult. Until now we didn't have a global observational basis for testing how well the models were predicting this particular aspect of climate. The paper attempts to do this using data from across six continents. Both the paper itself and our press release  go to considerable efforts to provide a balanced report on the research. 

We have a saying in the UK that you shouldn't throw the baby out with the bath-water. There are plenty of people around who jump on any evidence that the models aren't as good as we would like, and instantly move to reject the whole enterprise of climate modelling. We all know the models have to get better, and to get better, scientists need to identify aspects where the models fail. Sometimes communicating that process isn't easy.

Christopher M. Taylor, Richard A. M. de Jeu, Fran├žoise Guichard, Phil P. Harris & Wouter A. Dorigo Afternoon rain more likely over drier soils’ was published in Nature on 12 September 2012.  DOI 10.1038/nature11377

Wednesday, 12 September 2012

Invasive Alien Species: From Data to Decisions

Guest blog by Dr Helen Roy, Ecological Entomologist at the Centre for Ecology & Hydrology, who is a coordinator of the DAISIE (Delivering Alien Invasive Species Inventory for Europe) project.
Invasive Alien Species (IAS) pose a major threat to biodiversity, society, human-health, well-being and the economy. In Europe the economic impact is estimated as 12.5 billion eurosbut extrapolated costs suggest it is over 20 billion euros annually.  Europe has committed to tackling IAS through the recently published EU Biodiversity Strategy to 2020.
Over the next three days (12-14 September 2012) scientists will gather at Neobiota 2012 (taking place in Pontevedra, Spain) - a conference dedicated to research on invasive alien species.  The theme of Neobiota, from data to decisions, provides a perfect context for providing an update on DAISIE (Delivering Alien Species Inventories for Europe). 
DAISIE is an online database providing information on alien species in Europe.  It is unique in many regards.  It is the most comprehensive database on alien species providing information on more than 12,000 alien species**.  It also represents a community of dedicated experts committed to addressing the threat of invasive alien species through the provision of high quality and relevant information available for all. 

DAISIE website homepage at

DAISIE is maintained by the NERC Centre for Ecology & Hydrology (CEH) but relies on collaboration with many alien species experts across Europe to ensure it remains current.  The time, commitment and enthusiasm of the DAISIE alien species experts is inspiring.  So it is with a sense of pride that Jan Pergl (Institute of Botany ASCR, Czech Republic) and I will relaunch DAISIE at Neobiota today (12 September). 
We will have an opportunity to reflect on the many successes of DAISIE, from peer-reviewed publications and books, to the major part DAISIE has played in contributing to strategies on invasive alien species over the last few years.  It is also a time to look forward and to highlight the future role of DAISIE as an information system that will both underpin effective decision making across Europe and provide a rich resource for researchers and invasion biologists. 
We look forward to welcoming new alien species experts to the DAISIE community and invite them to contribute to this impressive database.
Dr Helen Roy

Additional information

* Kettunen et al (2009) Assessment of the impacts of IAS in Europe and the EU. Institute for European Environmental Policy. 
** What is an alien species? Alien species, also known as exotic, introduced or non-native species, are species, subspecies or lower taxon occurring outside of the range they occupy naturally or could not occupy without direct or indirect introduction or care by humans. Although the majority of alien species cause no harm, some alien species spread very rapidly and can harm biological diversity, human health, and/or economic and aesthetic values. These harmful species are called invasive alien species. More information at DAISIE.