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. These changes are of similar magnitude to changes over the last 9000 years. Some rivers (Nile, Syr Darya) experienced strong reductions in discharge over the last 9000 years (17 56), but show much smaller responses to future warming. The simulation results for the last 9000 years are validated with independent proxy data. forcing mechanism of long-term climate variability [Opsteegh et al., 1998; Renssen et al., 2005]. These inso-lation variations differ per latitude and per season. In the Northern Hemisphere (NH), the seasonal insolation contrast was larger at 9000 years BP than today, with more insola-tion being received in summer (between 25 and 45 W m 2 more than today) and less in winter (10 to 25 W m 2 less than today). At 9000 years BP the seasonal insolation contrast was smaller in the Southern Hemisphere (SH) than it was at that time in the NH. In response to the NH summer insolation maximum, the early Holocene (9000 8000 BP)
per
century on a yearly basis.
and 100 of the true (simulated) millennial history. Whether or not these results extend to the real-world case, i.e. whether or not the MBH98 and relative approaches are robust.
(20 to 40) by 2100 from their 21st century mean values. Large declines in 21st century snow cover frequency (up to 50) and snow mass (up to 100 kg m 2 ) arise during fall, winter, and spring over southern Canada and the northern United States, the Western Cordillera of North America, and western Eurasia compared to the 20th century CM2 simulations.
of the amplitude variations and may be related to the sunspot cycle, which affects summer temperature over Egypt. Other harmonics may be related to El Nino southern oscillation (ENSO) cycle, quasi-biennial oscillation (QBO) cycle, and solar inertial motion cycle. Each of them contribute approximately 9 to summer temperature in Egypt and so their influence on summer temperatures in the area is not so much.
with conver-sion of pasture to forest on an annual basis. Both pastured sites showed similar annual soil respi-ration rates. Comparisons of the paired forests, one coniferous and the other broadleaf, only showed a significant difference over one annual cycle. Enhanced soil respiration in pastures may be the result of either enhanced root respiration and/or microbial respiration. Differences in pasture forest soil respiration were primarily observed during the July through September summer period at all sites, suggesting that this is the critical period for observing and documenting differences. Evaluation of the soil microclimatic controls on soil respiration suggest that soil tem-perature exerts a major control on this process, and that examining these relationships on a sea-sonal rather than weekly basis provides the strongest relationships in poorly drained soils.
to global surface warming of 0.40 +- 0.04 K from 1980 to 2002. But their claim depends crucially on the solar irradiance time series adopted for this period; nor is it reproduced by a multivariate linear regression analysis of the solar, anthropogenic and climate data.
In summary, rather than minimally contributing 
of global mean surface warming from 1980 to 2002, the Willson and Mordvinov [2003] irradiance com-posite accounts for 
or less of this warming. Since secular change in solar irradiance is negligible in recent decades according to the Frohlich and Lean [2004] com-posite, it is entirely possible that the Sun has contributed little to the recent global warming trend.
during the course of the Little Ice Age (LIA) ( 1200 1850 A.D.), equivalent to a salinity increase of 0.8 1.5. On the Great Bahama Bank, where surface waters are influenced by the North Atlantic subtropical gyre, d 18 Ow increased by 0.3 during the last 200 years. Although a portion ( 0.1 ) of this shift may be an artifact of anthropogenically driven changes in surface water S CO2 , the remaining d 18 Ow signal implies a 0.4 1 increase in salinity after 200 years B.P. The simplest explanation of the d 18 Ow data is southward migration of the Atlantic Hadley circulation during the LIA. Scaling of the d 18 Ow records to salinity using the modern low-latitude d 18 Ow -S slope produces an unrealistic reversal in the salinity gradient between the two sites. Only if d 18 Ow is scaled to salinity using a high-latitude d 18 Ow -S slope can the records be reconciled. Variable atmospheric 14 C paralleled Dry Tortugas d 18 Ow , suggesting that solar irradiance paced centennial-scale migration of the Inter-Tropical Convergence Zone and changes in Florida Current salinity during the last millennium.
[Rahmstorf 2006]
Argues that the [von Storch et al. 2004] arguments about variance underestiimation are wrong and that the HADcm results actually contradict the message of the paper
Last millennium. Climate reconstructions
, depending on depth, frequency and subsurface thermophysical properties. The implications of our results are straightforward: the corruption of subsurface temperatures can affect model assessments of soil microbial activity, vegetation changes, freeze-thaw cycles, and hydrologic dynamics. It is uncertain, however, whether the reported effects will have large enough impacts on land-atmosphere fluxes of water and energy to affect atmospheric simulations.
increase in prevalence. Climatic conditions favoring plague apparently existed in this region at the onset of the Black Death as well as when the most recent plague pandemic arose in the same region, and they are expected to continue or become more favorable as a result of climate change. Threats of outbreaks may thus be increasing where humans live in close contact with rodents and fleas (or other wildlife) harboring endemic plague.
of the total summer temperature variability over the Mediterranean area. The positive phase of the first most important canonical mode is associated with block-ing conditions, subsidence and stability related to warm Mediterranean summers. The second CCA mode shows an east-west dipole of the Mediterranean summer air temperature connected by a combination of a trough as well as an extended ridge over the western and eastern parts of the Mediterranean, respectively. It is mainly the first mode which is responsible for the significant 0.4
C warming over the last 50 years of the twentieth century. In the context of the last 500 years it comes apparent that the hot summers of the decade 1994-2003 seem to be unprecedented. The hottest larger Mediterranean summer over the last half millennium was in 2003, in agreement with findings from the whole of Europe. It is found that around 30 of the total Mediterranean October to March precipitation variability can be ac-counted for by the combination of four large-scale geopotential height fields and sea level pressure. Results show that the North Atlantic Oscillation (NAO) seems to play an important role in interannual to centennial low frequency variability of wet season precipitation over the studied area. In the western and northern part, the correlation between precipitation and the NAO is negative, whereas for the south-eastern part mostly positive correlations have been found. The analysis further reveals that since the mid-nineteenth century precipitation steadily increased with a maximum in the 1960s and decreased since then. The second half of the twentieth century shows a general downward trend of 2.2 mm/month/decade.