Search

Climate change, involving changes in mean climate and climatic variability, is expected to severely affect agriculture and there is a need to assess its impact in order to define the appropriate adaptation strategies to cope with. In this paper, we projected a scenario of European agriculture in a +2°C (above pre-industrial levels) world in order to assess the potential effect of climatic change and variability and to test the effectiveness of different adaptation options. For this purpose, the outputs of HadCM3 General Circulation Model (GCM) were empirically downscaled for current climate (1975-2005) and a future period (2030-2060), to feed a process-based crop simulation model, in order to quantify the impact of a changing climate on agriculture emphasising the impact due to changes in the frequency of extreme events (heat waves and drought). The same climatic dataset was used to compare the effectiveness of different adaptations to a warmer climate strategies including advanced or delayed sowing time, shorter or longer cycle cultivar and irrigation. The results indicated that both changes in mean climate and climate variability affected crop growth resulting in different crop fitting capacity to cope with climate change. This capacity mainly depended on the crop type and the geographical area across Europe. A +2°C scenario had a higher impact on crops cultivated over the Mediterranean basin than on those cultivated in central and northern Europe as a consequence of drier and hotter conditions. In contrast, crops cultivated in Northern Europe generally exhibited higher than current yields, as a consequence of wetter conditions, and temperatures closer to the optimum growing conditions. Simple, no-cost adaptation options such as advancement of sowing dates or the use of longer cycle varieties may be implemented to tackle the expected yield loss in southern Europe as well as to exploit possible advantages in northern regions. [ABSTRACT FROM AUTHOR]

This paper reviews the knowledge on effects of climate change on agricultural productivity in Europe and the consequences for policy and research. Warming is expected to lead to a northward expansion of suitable cropping areas and a reduction of the growing period of determinate crops (e.g. cereals), but an increase for indeterminate crops (e.g. root crops). Increasing atmospheric CO2 concentrations will directly enhance plant productivity and also increase resource use efficiencies.In northern areas climate change may produce positive effects on agriculture through introduction of new crop species and varieties, higher crop production and expansion of suitable areas for crop cultivation. Disadvantages may be an increase in the need for plant protection, the risk of nutrient leaching and the turnover of soil organic matter. In southern areas the disadvantages will predominate. The possible increase in water shortage and extreme weather events may cause lower harvestable yields, higher yield variability and a reduction in suitable areas for traditional crops. These effects may reinforce the current trends of intensification of agriculture in northern and western Europe and extensification in the Mediterranean and southeastern parts of Europe.Policy will have to support the adaptation of European agriculture to climate change by encouraging the flexibility of land use, crop production, farming systems etc. In doing so, it is necessary to consider the multifunctional role of agriculture, and to strike a variable balance between economic, environmental and social functions in different European regions. Policy will also need to be concerned with agricultural strategies to mitigate climate change through a reduction in emissions of methane and nitrous oxide, an increase in carbon sequestration in agricultural soils and the growing of energy crops to substitute fossil energy use. The policies to support adaptation and mitigation to climate change will need to be linked closely to the development of agri-environmental schemes in the European Union Common Agricultural Policy.Research will have further to deal with the effect on secondary factors of agricultural production, on the quality of crop and animal production, of changes in frequency of isolated and extreme weather events on agricultural production, and the interaction with the surrounding natural ecosystems. There is also a need to study combined effects of adaptation and mitigation strategies, and include assessments of the consequences on current efforts in agricultural policy to develop a sustainable agriculture that also preserves environmental and social values in the rural society. [Copyright &y& Elsevier]

Chironomids preserved in a sediment core from Lago di Origlio (416ma.s.l.), a lake in the foreland of the Southern Swiss Alps, allowed quantitative reconstruction of Late Glacial and Early Holocene summer temperatures using a combined Swiss-Norwegian temperature inference model based on chironomid assemblages from 274 lakes. We reconstruct July air temperatures of ca. 10 °C between 17 300 and 16 000 cal yr BP, a rather abrupt warming to ca. 12.0 °C at ca. 16 500-16 000 cal yr BP, and a strong temperature increase at the transition to the Bølling/Allerød interstadial with average temperatures of about 14 °C. During the Younger Dryas and earliest Holocene similar temperatures are reconstructed as for the interstadial. The rather abrupt warming at 16 500-16 000 cal yr BP is consistent with sea-surface temperature as well as speleothem records, which indicate a warming after the end of Heinrich event 1 (sensu stricto) and before the Bølling/Allerød interstadial in southern Europe and the Mediterranean Sea. Pollen records from Origlio and other sites in southern Switzerland and northern Italy indicate an early reforestation of the lowlands 2000-1500 yr prior to the large-scale afforestation of Central Europe at the onset of the Bølling/Allerød period at ca. 14 700-14 600 cal yr BP. Our results suggest that these early afforestation processes in the formerly glaciated areas of northern Italy and southern Switzerland have been promoted by increasing temperatures. [ABSTRACT FROM AUTHOR]