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Introducing ESurf

3 Apr

ESurf, more formally known as Earth Surface Dynamics is the new open access journal from the EGU. Focussing on the processes that affect the Earth’s surface at all scales, ESurf aims to communicate the interactions of Earth surface processes with the lithosphere, biosphere, atmosphere, hydrosphere and pedosphere. Highlighting field measurements, remote sensing and experimental and numerical modeling of Earth surface processes.

The first issue of Earth Surface Dynamics!

As with most other EGU journals, Earth Surface Dynamics has an open review process, where the submitted papers are also available in an open access discussion forum (Earth Surface Dynamics Discussions). What’s more, because ESurf is the ‘new kid on the block’, all submission charges are currently waived, so it’s free to submit, free to access and free to use. Brilliant!

Take a look at the first issue here and to keep updated on the latest research in Earth Surface Dynamics, follow the journal on Twitter (@EGU_ESurf).

More information about the launch of this great open access journal is also available on the EGU website.

Geosciences column: The contribution of climate change to water scarcity in the MENA region

1 Feb

In this month’s Geoscience’s column, Alex Stubbings discusses the water scarcity problems in the Middle East and North Africa region and  the recent developments in modelling water resources here. 

The Middle East and North Africa (MENA) region is considered the most water-scarce region in the world. As such, the region faces a multitude of challenges in the 21st century including population growth, economic development, food production and climate change. With these challenges in mind, a team of researchers led by hydrologist Dr. Peter Droogers explored how “Water resources trends in the Middle East and North Africa towards 2050” will change over the first half of the 21st century. The study is published in EGU’s Open Access journal Hydrology and Earth System Sciences.

Presently, there exist huge spatial variations in water allocation, and the region as a whole is the driest and most water scarce region in the world. This is increasingly affecting the social and economic development of the region.  For example, the average water resource availability per capita is only marginally above the physical water availability of 1076 m3yr-1, compared to the world average of 8500 m3yr-1.

The prevailing arid conditions found within the area mean that over 85% of the MENA region can be considered desert. It follows that the region can be further subdivided into three distinct climate spaces: the Maghreb region, which constitutes North African countries with a Mediterranean climate, and is climatically heterogeneous; the Gulf Cooperation Countries located within the Middle East, and have a typical desert climate; and lastly, the Mashreq region, which includes countries that have a milder and wetter climate, such as Iraq and Syria.

The Middle East and North Africa (MENA) region (blue), (Source: Wikimedia Commons).

Therefore the lead question Droogers et al. focused on filling vital knowledge gaps. Indeed, they highlight that “a complete analysis on water demand and water shortage over the coming 50 year period based on a combined use of hydrological and water resource models, remote sensing and socio-economic changes has never been undertaken for the MENA region”. Moreover, they intend to achieve this by assessing water demand in the 22 MENA countries by taking into account the dynamics and uncertainties of climate change, demographic changes and economic development.

The team used two distinct models that covered a 50 year time period (2000–2050). Firstly, the PCR-GLOBWB (PC Raster Global Water Balance) hydrological model was run to determine the internal and external renewable water resources for present and future climate. And the second model employed was a water allocation model, referred to as the MENA Water Outlook Framework (MENA-WOF). This was chosen to analyse the linkage between renewable water resources and sectoral water demands, and utilises the Water Evaluation and Planning (WEAP) framework.

This approach allowed the research team to simulate the average hydrological conditions with great accuracy – best demonstrated by its ability to accurately model and replicate actual flows on the Blue Nile, White Nile and Atbora tributaries. The team singled this out as a key indicator of its robustness. They noted that other similar studies, to date, have yet to model these flow regimes accurately.

Long-term average annual observed and simulated flow (Source: Droogers et al., 2012).

Nevertheless, as with other empirical modelling studies the authors issue a caveat: that the results regarding water resources, derived through GCM output, should be interpreted with great care. The model predicts total water shortage will increase by 157 km3yr-1, while water supply and demand are only projected to increase by 132 km3yr-1.  In short, the overall trend is that all MENA region countries will see an increase in water shortages, as the increase in supply will not meet the growth in demand, except for Djibouti.

Droogers et al. naturally consider the contribution of climate change to water scarcity. Their results indicate that only 10% of the change in water demand will be attributed to climate change and the rest entirely due to socio-economic changes (under their average climate change scenario). Furthermore in the other two scenarios, wet and dry, socio-economic factors, again, are more important than the effects of climate change. However, they emphasise that despite the small contribution made by climate change its effects should still be taken into consideration when planning adaptation interventions.

The contribution of socio-economic changes and climate changes on total water demand in 2050 (Source: Droogers et al., 2012).

The findings presented here by Droogers et al. are unique. They have combined different data, models and tools in order to forecast changes in water demand and supply over a geographically diverse area. Despite this novel approach, a clear drawback of the study, recognised by the team, is that the spatial resolution is lower than the output for smaller geographical areas and utilising a single methodological approach would have allowed more in depth comparisons to be made between countries.

When looking at the wider landscape of climate change impacts and adaptation strategies the team refer to a World Bank study from 2010, which estimated the cost of adaptation for developing counties at 0.12% of GDP, with costs associated with adaptation increasing linearly with time. The authors offer a number of pragmatic solutions, which fall under the umbrella of ecological modernisation, highlighting the potential of desalination plants.

As a work in progress, Droogers and his team offer direction for future work. Firstly, they suggest that further research should be carried out at a higher spatial resolution, for instance, employing the same methodology but focusing on individual countries rather than on an entire region. And secondly, of the need to analyse potential adaptation strategies and the associated costs of implementing them within the region. Both directions have their merits, but with the uncertain nature of climate change makes it difficult to distinguish which step we should take next.

By Alex Stubbings

Geosciences column: Hazard perception – how great is the risk of a rockfall?

30 Jan

In this month’s Geoscience’s column, Sara Mynott discusses the geological hazards associated with climate warming and how recent research sheds new light on our understanding of rockfall frequency.

Rockfalls are the free-falling movement of bedrock material from a rock face, a phenomenon also encompassed by the terms ‘landslide’, ‘rockslide’ and ‘rock avalanche’. They range from small debris falls of only a few cubic-metres to large ‘bergsturz’ events of over 1 million metres-cubed. The number of rockfalls reported has increased in recent years and is often attributed to global warming, despite the lack of research in this area. The debate among scientists regarding the effect of climate change on geomorphic hazards has led to a lot of confusion among the media and hence, the public.

Climate change is expected to have numerous consequences for natural hazards and the IPCC has predicted that geomorphic hazards will increase in alpine regions as a result. However, recent research published in Natural Hazards and Earth Systems Science suggests that this may not be the case. In a recent assessment of Austrian rockfalls over the period 1990-2010, Oliver Sass and Manfred Oberlechner investigated how temperature influences their frequency. Their dataset was compiled from events that were large enough to be recorded in the media, restricting it to events that have the capacity to affect people and/or infrastructure. The Huben rockslide that occurred in 1999, which resulted in both the loss of alpine road access and the destruction of a local sawmill, presents one such example.

Rockfall in Huben, Austria, that occurred on 11 March 1999, far below the permafrost limit. This rockfall resulted in both the destruction of a sawmill and loss of road access (Source: Sass and Oberlechner, 2012).

Historical records of rockfalls are scarce, making predictions for the future a challenge and, until recently, little research on the temporal frequency of rockfall events had been carried out. This is partly due to the research focus on areas of permafrost, which cover less than 4 % of the Austrian Alps. Consequently, the relationship between surface temperature and rockslide frequency in permafrost regions is well-known. Permafrost, which exists at sub-zero temperatures, cements sediment together and gives it stability. Unsurprisingly, warming causes permafrost to degrade, leading to a loss of sediment stability and an increased risk of geomorphic hazards. The likelihood of these hazards occurring is a function of substrate type. However, areas of public interest (those with infrastructure) tend to be permafrost-free. In fact, 91% of the events studied were below the permafrost limit (less than 2100 m elevation).

Contrary to the IPCC’s predictions, the study found that there was no relationship between temperature and the number of rockfall events below the permafrost limit, nor was there any correlation between precipitation and rockfall frequency. The increasing settlements and infrastructure within the Alps means there is a greater risk of a geomorphic hazard occurring and the increase in availability of information means there appears to be more events than 20 years ago. Thus, the apparent increase in rockfall occurrence in recent years is likely to be due to a reporting bias.

Whilst there is no evidence for warming increasing the annual number of rockfalls, changes in seasonal weather patterns have resulted in a shift in their occurrence throughout the year. Rockfalls are generally more common in spring than at any other time of year as both the increase in water supply (through snowmelt and high precipitation rates) and high degree of freeze-thaw activity (also known as cryoturbation) destabilises the sediment. However, in recent decades, a greater proportion of rockfalls have occurred during the summer months, leading to a more even distribution of these hazards throughout the year.

Below the permafrost limit there is insufficient evidence to support the notion that increasing rockfall events are associated with climate warming. In fact, the study reveals that milder winters may even reduce the number of rockfalls outside areas of permafrost. Whilst Sass emphasises that these results are preliminary, they highlight the complexity of predicting the impacts of climate change and expose an alternative way in which it can affect hazardous earth processes.

By Sara Mynott, EGU Communications Officer

EGU Twitter Journal Club 5 — Policy briefing: Water resource resilience

8 Nov

It’s time for the fifth edition of the EGU’s Twitter Journal Club, our interactive online discussion about a timely scientific article. If you have not yet taken part in one of these discussions, read more about it in our introductory post and make sure to participate when we meet online next week! 

This time, we will be discussing the recent peer-reviewed policy briefing Water Resource Resilience, produced by the UK Parliamentary Office of Science & Technology (POST).

The discussion will take place on Twitter next Thursday 15 November at 14:00 CET, and you can take part by following the EGU’s Twitter account (@EuroGeosciences) and using the hashtag #egutjc5 on your tweets. Please email the EGU’s Science Communications Fellow Edvard Glücksman if you have any further questions.

Happy reading!

The availability of water resources is fundamental for society and economic activities. (Photo: Edvard Glücksman)

Water Resource Resilience

Published 17 September 2012 | POST notes POST PN 419

Summary. The availability of water resources is fundamental for society and economic activities. This POSTnote describes the reasons for uncertainties in water resource availability for future supply and demand and possible responses to managing these risks in the medium term.

Questions to think about:

1. How would you summarise this briefing in a tweet?

2. How does the framework presented here apply internationally, particularly in other European countries?

3. Why are Environmental Flow Indicators (EFIs) important?

4. What would you add to this paper, if given an extra two pages of space?

 

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