Causes,consequences and chronology of large‐magnitude palaeoflows in Middle and Late Pleistocene river systems of northwest Europe

This study examines the record of high‐palaeoflow phases in river systems in northwest Europe, investigating their causes (whether due to ‘unique’ events, such as the formation of the Dover Strait, or as ‘characteristic’ consequences of climate change), examining their consequences with regard to landscape evolution and possible effects on climate, and determining the chronology of key events. Large‐magnitude palaeoflows, more than an order‐of‐magnitude larger than present‐day flood peaks, are shown to be characteristic of rivers in this region at particular times within the Pleistocene. These events, the most recent of which were during Heinrich events 2 and 1 at ～25 and ～17 ka, were evidently caused by the combined effects of glacial outwash, rainfall, snowmelt and melting of permafrost in some proportion. They released such large volumes of water that the thermohaline circulation of the Atlantic Ocean, and thus the climate, may well have been affected. These large‐magnitude palaeoflows are thus a significant aspect of the Pleistocene Earth system that has hitherto gone unquantified. Copyright © 2010 John Wiley & Sons, Ltd.     

Contaminants in cetaceans from UK waters: status as assessed within the Cetacean Strandings Investigation Programme from 1990 to 2008

Since 1990, tissue samples from UK-stranded and -bycaught cetaceans have been available for study of contaminant burdens. These have been used to study spatial and temporal trends in concentrations in UK waters, and to investigate potential associations between contaminants and health status. We describe the current status of cetaceans (primarily harbour porpoises, Phocoena phocoena) in UK waters in relation to pollution. Concentrations of BDEs, HBCD, and the organochlorine pesticides are declining. In contrast, concentrations of CBs have plateaued following earlier reductions due to regulation of use, and further reductions are likely to take decades. Blubber PCB concentrations are still at toxicologically significant levels in many harbour porpoises and regularly occur at even higher levels in bottlenose dolphins and killer whales due to their higher trophic level in marine food chains. Further reductions in PCB inputs into the marine environment are needed to mitigate risk from PCB exposure in these species.     

Climatically controlled river terrace staircases: A worldwide Quaternary phenomenon

A comparison of fluvial terrace sequences from around the world, based on data collected as part of International Geoscience Programme (IGCP) Project No. 449, has revealed significant patterns. River terraces provide important records of uplift, which is essential for their formation, and of landscape evolution. Their cyclic formation, however, almost invariably seems to have been a response to climatic fluctuation. Sequences in the European core area of IGCP 449, which has the longest and most extensive research history, have been used as templates for worldwide comparison. There is evidence for a global acceleration of uplift at the time of, and perhaps in response to, the Mid-Pleistocene Revolution, when climatic fluctuation switched to 100 kyr Milankovitch cycles. Terraces formed prior to this generally consist of wide aggradational sheets that probably each represent formation over several 41 kyr cycles. Subsequently, river valleys became more steeply entrenched and terraces formed in response to the stronger 100 kyr climatic forcing, in many cases at approximately one per cycle. This paper uses the new data resource to explore differences between records in different climate zones, between sequences with variable numbers of Middle–Late Pleistocene terraces and between systems in which the all-important incision event has occurred in different parts of climatic cycles. Key records discussed include European examples from the Rhine, Thames, Somme, Dniester, Dnieper, Don, Volga and Aguas; from Asia the Gediz (Turkey) and Orontes (Syria); from North America, the South Platte and Colorado; from South Africa the Vaal and Sundays; from Australia the Shoalhaven; and from South America, the Amazon, Paraguay and tributaries of the Colorado and Negro.     

The SCUBA HAlf Degree Extragalactic Survey – VI. 350-μm mapping of submillimetre galaxies

A follow-up survey using the Submillimetre High-Angular Resolution Camera (SHARC-II) at 350 μm has been carried out to map the regions around several 850-μm-selected sources from the Submillimetre HAlf Degree Extragalactic Survey (SHADES). These observations probe the infrared (IR) luminosities and hence star formation rates in the largest existing, most robust sample of submillimetre galaxies (SMGs). We measure 350-μm flux densities for 24 850-μm sources, seven of which are detected at ≥2.5σ within a 10 arcsec search radius of the 850-μm positions. When results from the literature are included the total number of 350-μm flux density constraints of SHADES SMGs is 31, with 15 detections. We fit a modified blackbody to the far-IR (FIR) photometry of each SMG, and confirm that typical SMGs are dust-rich  ( M _dust≃ 9 × 10⁸ M_⊙)  , luminous  ( L _FIR≃ 2 × 10¹² L_⊙)  star-forming galaxies with intrinsic dust temperatures of ≃35 K and star formation rates of  ≃400 M_⊙ yr⁻¹  . We have measured the temperature distribution of SMGs and find that the underlying distribution is slightly broader than implied by the error bars, and that most SMGs are at 28 K with a few hotter. We also place new constraints on the 350-μm source counts, N ₃₅₀(>25 mJy) ∼ 200–500 deg⁻².     

How harmful are restrictions on adapting to climate change?

The dominant assumption in economic models of climate policy remains that adaptation will be implemented in an optimal manner. There are, however, several reasons why optimal levels of adaptation may not be attainable. This paper investigates the effects of suboptimal levels of adaptation caused by different types of adaptation restrictions, on the composition and level of climate change costs and on welfare. We find that especially restrictions to the effectiveness of adaptation at more extreme levels of climate change can be very harmful. Furthermore we show that the potential of mitigation to offset suboptimal adaptation varies from being essential in case adaptation becomes ineffective at higher temperature increases, to being largely ineffective in case of short-term inaction. However, in all cases the short-term recommendation is to increase mitigation levels slightly above what is normally recommended, and to keep mitigation policies flexible enough to be able to respond when adaptation restrictions become more prominent. It is clear that by reducing adaptation restrictions, in combination with adjusting the optimal level of mitigation may keep the costs of adaptation restrictions limited, and thus generally it is very harmful to ignore existing restrictions on adaptation when devising (efficient) climate policies.     

Forecasting Natural Aquifer Discharge Using a Numerical Model and Convolution

If the nature of groundwater sources and sinks can be determined or predicted, the data can be used to forecast natural aquifer discharge. We present a procedure to forecast the relative contribution of individual aquifer sources and sinks to natural aquifer discharge. Using these individual aquifer recharge components, along with observed aquifer heads for each January, we generate a 1‐year, monthly spring discharge forecast for the upcoming year with an existing numerical model and convolution. The results indicate that a forecast of natural aquifer discharge can be developed using only the dominant aquifer recharge sources combined with the effects of aquifer heads (initial conditions) at the time the forecast is generated. We also estimate how our forecast will perform in the future using a jackknife procedure, which indicates that the future performance of the forecast is good (Nash‐Sutcliffe efficiency of 0.81). We develop a forecast and demonstrate important features of the procedure by presenting an application to the Eastern Snake Plain Aquifer in southern Idaho.     

Sharing the burden of financing adaptation to climate change

Climate change may cause most harm to countries that have historically contributed the least to greenhouse gas emissions and land-use change. This paper identifies consequentialist and non-consequentialist ethical principles to guide a fair international burden-sharing scheme of climate change adaptation costs. We use these ethical principles to derive political principles – historical responsibility and capacity to pay – that can be applied in assigning a share of the financial burden to individual countries. We then propose a hybrid ‘common but differentiated responsibilities and respective capabilities’ approach as a promising starting point for international negotiations on the design of burden-sharing schemes. A numerical assessment of seven scenarios shows that the countries of Annex I of the United Nations Framework Convention on Climate Change would bear the bulk of the costs of adaptation, but contributions differ substantially subject to the choice of a capacity to pay indicator. The contributions are less sensitive to choices related to responsibility calculations, apart from those associated with land-use-related emissions. Assuming costs of climate adaptation of USD 100 billion per year, the total financial contribution by the Annex I countries would be in the range of USD 65–70 billion per year. Expressed as a per capita basis, this gives a range of USD 43–82 per capita per year.     

Five centuries of Stockholm winter/spring temperatures reconstructed from documentary evidence and instrumental observations

Historical documentary sources, reflecting different port activities in Stockholm, are utilised to derive a 500-year winter/spring temperature reconstruction for the region. These documentary sources reflect sea ice conditions in the harbour inlet and those series that overlap with the instrumental data correlate well with winter/spring temperatures. By refining dendroclimatological methods, the time-series were composited to a mean series and calibrated (1756–1841; r ²?=?66%) against Stockholm January–April temperatures. Strong verification was confirmed (1842–1892; r ²?=?60%; RE/CE?=?0.55). By including the instrumental data, the quantified (QUAN) reconstruction indicates that recent two decades have been the warmest period for the last 500 years. Coldest conditions occurred during the 16th/17th and early 19th centuries. An independent qualitative (QUAL) historical index was also derived for the Stockholm region. Comparison between QUAN and QUAL shows good coherence at inter-annual time-scales, but QUAL distinctly appears to lack low frequency information. Comparison is also made to other winter temperature based annually resolved records for the Baltic region. Between proxy coherence is generally good although it decreases going back in time with the 1500–1550 period being the weakest period—possibly reflecting data quality issues in the different reconstructions.