Severe Historical Droughts Carved on Rock in the Yangtze

Abstract The White Crane Ridge (WCR) Rock Fish, now submerged under the backwater of the Three Gorges Reservoir in the Yangtze River, are affirmed as one of the earliest hydrologic observations ever made in any large river in the world. The usually in-water monument provides highly valuable historical records of severe droughts in the upper Yangtze over the last 1,200 years. This article updated the historical drought chronology previously developed based on the WCR inscriptions, which can be applied in assessment of extreme climatic and hydrological risks, and also made a preliminary analysis of changes of the severe drought frequency during the last thousand years in the upper Yangtze. The analysis shows that the severe droughts occurred more frequently during the Medieval Climate Anomaly (MCA), relatively less so during the Little Ice Age (LIA), and once again more often under the background of modern global warming. It was suggested that a generally warmer Euro-Asian continent during the MCA was in favor of the stronger East Asian summer monsoon, and the resulting less precipitation and more severe droughts of the Yangtze and the lower water level at the Three Gorges area on the centennial scale, and vice versa for the period of the LIA. The results would help in understanding the causes and mechanisms of the regional climate change and variability, and also in taking measures in the fields of the watershed management to cope with the long-term change in climatic and hydrologic droughts.

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Regional climate change after the commissioning of the Three Gorges Dam: a case study for the middle reaches of the Yangtze River

Climate Research ◽

10.3354/cr01504 ◽

2018 ◽

Vol 75 (1) ◽

pp. 33-51 ◽

Cited By ~ 1

Author(s):

F Ge ◽

K Mao ◽

Y Jiang ◽

L Wang ◽

T Xu ◽

...

Keyword(s):

Climate Change ◽

Yangtze River ◽

Regional Climate ◽

Regional Climate Change ◽

Three Gorges Dam ◽

Three Gorges ◽

The Yangtze River ◽

The Three Gorges ◽

The Three Gorges Dam

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Using a Complex Network to Analyze the Effects of the Three Gorges Dam on Water Level Fluctuation in Poyang Lake

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi8110470 ◽

2019 ◽

Vol 8 (11) ◽

pp. 470 ◽

Cited By ~ 2

Author(s):

Ning ◽

Zhou ◽

Cheng ◽

Ye ◽

Shen

Keyword(s):

Water Level ◽

Complex Network ◽

Frequency Distribution ◽

Water Level Fluctuation ◽

Three Gorges Dam ◽

Severe Drought ◽

Level Fluctuation ◽

Three Gorges ◽

The Three Gorges ◽

The Three Gorges Dam

Because the Three Gorges Dam (TGD) has disturbed the normal hydrological regime downstream, analyzing the influence of the TGD on water level fluctuation is of great importance to ecological planning. The distribution and dynamic of the water level before and after the TGD were analyzed using frequency distribution and a complex network. Frequency distribution was unimodal before the TGD, and the peak ranged from 13–15 m. Frequency distribution was bimodal after TGD and two peaks ranged from 9–10 m and 16–17 m. The number of days when the water level was above warning level was reduced, and it was increased when the water level was below the ecological level. Further, the TGD had little effect on the number of days of rapid water level rising, which mainly existed during the flood season. However, this imposed a greater influence on the number of days of rapid water level decline, which implies a weaker intensity of the recession process, along with a longer duration. Thirdly, in winter and spring, the water level after the TGD was lower than that before the TGD by approximately 1 m. In summer, the number of days when the water level was above warning level was reduced. In autumn, the frequency distribution changed from unimodal to bimodal. The TGD has the greatest influence during the winter, which resulted in a lower water level and more severe drought.

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Selecting Ensemble Members to Provide Regional Climate Change Information

Journal of Climate ◽

10.1175/jcli-d-11-00526.1 ◽

2012 ◽

Vol 25 (20) ◽

pp. 7100-7121 ◽

Cited By ~ 84

Author(s):

Carol F. McSweeney ◽

Richard G. Jones ◽

Ben B. B. Booth

Keyword(s):

Climate Change ◽

Summer Monsoon ◽

Dynamical Downscaling ◽

Asian Summer Monsoon ◽

Regional Climate ◽

Full Range ◽

Regional Climate Change ◽

Climate Projections ◽

Similar Data ◽

Asian Summer

Abstract Climate model ensembles, such as the Coupled Model Intercomparison Project, phase 3 (CMIP3), are used to characterize broadscale ranges of projected regional climate change and their impacts. The 17-member Hadley Centre perturbed physics GCM ensemble [Quantifying Uncertainty in Model Predictions (“QUMP”)] extends this capability by including data enabling dynamical downscaling of these ranges, and similar data are now being made available from the CMIP phase 5 (CMIP5) GCMs. These raise new opportunities to provide and apply high-resolution regional climate projections. This study highlights the importance of employing a well-considered sampling strategy from available ensembles to provide scientifically credible information on regional climate change while minimizing the computational complexity of ensemble downscaling. A subset of the QUMP ensemble is selected for a downscaling program in Vietnam using the Providing Regional Climates for Impacts Studies (PRECIS) regional climate modeling system. Multiannual mean fields from each GCM are assessed with a focus on the Asian summer monsoon, given its importance to proposed applications of the projections. First, the study examines whether any model should be eliminated because significant deficiencies in its simulation may render its future climate projections unrealistic. No evidence is found to eliminate any of the 17 GCMs on these grounds. Second, the range of their future projections is explored and five models that best represent the full range of future climates are identified. The subset characterizes the range of both global and regional responses, and patterns of rainfall response, the wettest and driest projections for Vietnam, and different projected Asian summer monsoon changes. How these ranges of responses compare with those in the CMIP3 ensemble are also assessed, finding differences in both the signal and the spread of results in Southeast Asia.

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Little Ice Age glaciers and climate in the Mediterranean mountains: a new analysis

Cuadernos de Investigación Geográfica ◽

10.18172/cig.3362 ◽

2018 ◽

Vol 44 (1) ◽

pp. 15 ◽

Cited By ~ 16

Author(s):

P.D. Hughes

Keyword(s):

Climate Change ◽

Little Ice Age ◽

Regional Climate ◽

Regional Climate Change ◽

Climatic Conditions ◽

Ice Age ◽

Glacier Mass Balance ◽

High Atlas ◽

Mediterranean Mountains ◽

The Mediterranean

Glaciers were common across the Mediterranean mountains during the Little Ice Age. In parts of Turkey some glaciers were several kilometres longer than they are today, whilst in the Pyrenees glaciers were up to several hundred metres longer. In the wettest Mediterranean mountains, such as the Dinaric Alps, many small glaciers and perennial snow patches would have been present. Even in driest and most southerly mountains, such as the High Atlas, small glaciers and perennial snowfields were present. This paper examines the evidence from these two contrasting regions (the western and southern Balkans and the High Atlas) and the climatic significance of glaciers in these areas during the Little Ice Age. Particular focus is given on the climatological controls on glacier mass balance in different climatic conditions. Glaciers in cold and dry climates exhibit different sensitivity to regional climate change compared with glaciers in cold and wet climates. In addition, the factors controlling ablation of glaciers in different climatic regimes can differ considerably, especially the relative contributions and effects of melting and sublimation. All Mediterranean mountain glaciers were strongly controlled by local topoclimatic factors. Avalanche-fed glaciers have proven to be the most resilient to climate change and dramatically increased accumulation from avalanching snow explains the surviving glaciers in the Dinaric Alps and the semi-perennial snow fields of the High Atlas. In addition, geology as well as landscape morphology inherited from Pleistocene glaciations plays a role in explaining the patterns of Little Ice Age glacier distribution and especially the patterns of retreat and survival of these glaciers. The resilience of some of the last remaining Mediterranean glaciers, in the face of warming climate, presents a contradiction and comparisons between glaciers gone and those that remain provides important insight into the future of similar glaciers globally.

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