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The paper presents new data and reviews previously obtained results on the late glacial to Holocene history of peatlands in the southern part of the Baikal region under conditions of regional climate changes. To better understand climate signals, we have combined vegetation and geochemical variation data in 4.6 m thick peat deposits in the Vydrino bog located on the Tankhoi piedmont plain south of Lake Baikal. The territory has been swamped since 13.1 cal ka BP when the peatland started developing as a fen upon a sedimentary substrate. The 13.1–9.5 cal kyr climate record included two events of warming separated by an excursion of dry cold climate. Warming continued till 9.0 cal ka BP and eutrophic peat formation occurred in favorable temperature and moisture conditions. Another warming episode between 9.0 and 8.4 cal ka BP ended up with the Holocene climate optimum while the bog became mesotrophic. About 7.3–6.5 cal ka BP, the temperature and moisture inputs were no longer optimal for fir and spruce forests in the Vydrino area, which led to dramatic changes in landscape and vegetation. The wet and warm climate gradually became drier and colder from 6.5 to 2.3 cal ka BP, with a brief warm excursion about 5.5–5.3 cal ka BP. The peat deposition was interrupted in a cold climate from ∼2.3 cal ka BP to ∼0.7 cal ka BP, and the bog became oligotrophic afterwards. The newly obtained data allowed us to compare the paleoclimatic indicators available for the south Baikal region to determine their compatibility and inconsistency. In addition, we provide a general view to the quality of the climate and environmental reconstructions in the Baikal region by comparison of the data on its peatland study. [ABSTRACT FROM AUTHOR]

Rate of global eustatic sea-level rise during the Holocene Epoch has been identified as the principle cause of observed changes or inferred evolution of nontectonic coastal systems in mid- to low-latitude areas. The rate of rise is now three times faster than it was for the past several thousand years and similar to values associated with the middle Holocene marine transgression. This acceleration can be attributed to human-caused global warming. In this investigation, the effects of accelerating sea-level rise on coastal sedimentary environments of the SE Saline Everglades were quantified. The results reveal historic changes to coastal habitat, sedimentation, and stratigraphy that are transgressive. These changes initiated during the early 20th century and are attributed to accelerating sea-level rise. As this acceleration and the resulting geologic record is a suspected consequence of human-induced global warming, the paper concludes with a discussion of the relevance of these observations, in tandem with others, to the current debate over the utility and use of the proposed Anthropocene. [ABSTRACT FROM AUTHOR]

China is the country with the most population in the world, and its climate is extremely diverse due to tremendous differences in latitude, longitude, and altitude, ranging from tropical in the far south to subarctic in the far north and alpine in the higher elevations of the Qinghai-Tibetan Plateau. Accurate assessment of its modern climate change is conductive to addressing global warming threat. Along with the development of Past Global Changes (PAGES) research, the focus has changed from paleo-climate reconstructions to using paleo-data for assessing the present and predicting the future. Previous studies have been devoted to climate change assessment using modern climate observations and simulations. This paper presents a new assessment approach based on the mid-Holocene, which provides a naturally oriented warming that can be compared to modern human-made global warming. A variety of climatic data, including modern observations, paleo-climate records, CMIP5 (Coupled Model Intercomparison Project Phase 5) and PMIP3 (Paleoclimate Modelling Intercomparison Project 3) simulations, as well as lake level models, were applied in this synthesis. Numerical climate classification was introduced to evaluate climate change impacts to Chinese climate zones on various time scales. The results show that winter and summer seasons have different response to the naturally oriented mid-Holocene warming but human-made global warming makes the warming trend appear in all seasons. Temperate and continental dry winter climates expand dramatically during the mid-Holocene warm period; however, the future global warming could have few impacts to Chinese climate zones. Furthermore, the East Asian summer monsoon was strengthened obviously by the mid-Holocene warm climate and strong low-latitude insolation. There is no consistent trend both for the winter and summer monsoon on the background of human-made global warming. In this study, a new benchmark was established based on paleo-climate to evaluate the impacts of human-made global warming. [ABSTRACT FROM AUTHOR]

Global climate change and its possible ecological consequences have become the focused issue (IPCC, 2007; Mann et al., 2008; Ding et al., 2009). The Holocene contains the analogous characteristic of future climatic change and the continuous agriculture activity, providing the ideal “similar pattern” for studying the climate change and human adaption and impact in the future. Based on the recent studies of stalagmite, ice core, ocean, and lake etc., the paper introduces the new progress in the Holocene climate and agriculture research in China as follows: (1) Discuss the variability, amplitude, and unstable characteristic of climate, as well as the abrupt events and mechanisms of climate. (2) Analyze the botanical index records for studying the early agriculture. (3) Review the agricultural origin, expanding, and development. (4) Reveal the style and intensity of early agriculture and understand the agricultural impact and adaption to the environmental changes. (5) Introduce ongoing research projects in China and emphasize the significance of increasing the dating precision and the indicative effectiveness of proxies. (6) Realize how the ecosystem and environmental factors respond to the increasing temperature process, understand how the human adapt to the rapid climate change, and provide the scientific basis for assessing the effects of climate change and the human adaption in the future. [ABSTRACT FROM AUTHOR]

This paper reviews both the recent and longer-term (Holocene) ecological history of coral reefs in the South China Sea (SCS). (1) Local ecological monitoring since the 1960s shows that the coral reefs in the South China Sea have declined dramatically, reflecting the rapid decrease of living coral cover and the great loss of symbiotic zooxanthellae. Collectively, this has led to a significant decrease of annual CaCO production. Heavy anthropogenic activities and global warming are recognized as major triggers of the observed coral reef degradation. Observations show that the modern coral reefs in the SCS are a source of atmospheric CO in summer. (2) Coral reefs of the SCS have been widely used to reveal longer-term environmental variations, including Holocene high-resolution sea surface temperature (SST) and abrupt climate events, millennial-scale El Niño variations, millennial- and centennial-scale sea level oscillations, strong and cyclic storm activities, East Asian monsoon intensities, variation in seawater pH, and recent seawater pollution. (3) Coral reefs of the southern SCS have experienced repeated episodes of bleaching over the last 200 years due to high SST and intense El Niño events; coral reefs of the northern SCS suffered high levels of mortality during several abrupt winter cold-water bleaching events during the middle Holocene warm period. On average, recovery after the middle Holocene cold-bleaching took 20-30 years; recovery following other middle Holocene environmental stresses took approximately 10-20 years. Such findings have significantly contributed to the understanding of the present ecological pressures faced by the coral reefs in the SCS, the histories of Holocene climate/environment changes, and the long-term models of coral reef responses to various past environmental changes. [ABSTRACT FROM AUTHOR]

Understanding past sea levels is essential to respond to the challenges of climate change. In the Pacific and Tasman, sea level has been up to 1.5 m higher during the mid-Holocene, similar to the predictions of some global warming models. Within New Zealand the knowledge of sea-level movements, especially during the recent past is poor, with the last major investigation being conducted 20 years ago. This paper reviews the state of local understanding of higher sea levels and suggests regions for further study and new methods of analysis to understand the nature of sea-level change in New Zealand. [ABSTRACT FROM AUTHOR]

Aim The assumedly anomalous occurrence of savannas and forest–savanna mosaics in the Gran Sabana – a neotropical region under a climate more suitable for tropical rain forests – has been attributed to a variety of historical, climatic, and anthropogenic factors. This paper describes a previously undocumented shift in vegetation and climate that occurred during the early Holocene, and evaluates its significance for the understanding of the origin of the Gran Sabana vegetation. Location A treeless savanna locality of the Gran Sabana (4°30′–6°45′ N and 60°34′–62°50′ W), in the Venezuelan Guayana of northern South America, at the headwaters of the Caroní river, one of the major tributaries of the Orinoco river. Methods Pollen and charcoal analysis of a previously dated peat section spanning from about the Pleistocene/Holocene boundary until the present. Results Mesothermic cloud forests dominated by Catostemma (Bombacaceae) occupied the site around the Pleistocene/Holocene boundary. During the early Holocene, a progressive but relatively rapid trend towards savanna vegetation occurred, and eventually the former cloud forests were replaced by a treeless savanna. Some time after the establishment of savannas, a marked increase in charcoal particles indicates the occurrence of the first local fires. Main conclusions The occurrence of cloud forests at the Pleistocene/Holocene boundary contradicts the historical hypothesis according to which the Gran Sabana is a relict of the hypothetical widespread savannas that have been assumed to have dominated the region during the last glaciation. The first local fires recorded in the Holocene were on savanna vegetation, which is against the hypothesis of fire as the triggering factor for the establishment of these savannas. Climate change, in the form of global warming and a persistently drier climate, emerges as the most probable cause for the forest–savanna turnover. [ABSTRACT FROM AUTHOR]

Mediterranean ecosystems contain some of the highest levels of plant diversity of any region on Earth and are amongst those believed to be most at risk from the consequences of global warming. Yet such ecosystems are not static and have responded to environmental changes at a variety of scales and from a variety of causes, particularly climatic and anthropogenic. The purpose of this paper is to review recent research on environmental change and ecosystem response. Long-term records are available to analyse changes over glacial-interglacial cycles, while high resolution records show the sensitivity and coupling of Mediterranean, North Atlantic and Greenland records. For the Holocene, there is continued debate about the relative impact of anthropogenic activity, but there is also increasing recognition that mediterraneantype ecosystems should not be regarded as fragile, degraded landscapes, but are disturbanceadapted. Nevertheless, conservation measures face increasing challenges from contemporary climate change and human pressures. Some insights into the identification of refugial areas, either in glacial times or for present-day conservation purposes, come from molecular biogeographical studies of past faunal and floral distribution. [ABSTRACT FROM AUTHOR]