Eternal Climate Change Patterns and the Causes and Countermeasures of Global Climate Change

It is an objective fact that the weather is unpredictable.Even the famous meteorologist,Academician Chu Ko Chen,has only a partial understanding of the changing laws of wind and rain.Even though ancient people summarized the 24 solar terms by observing the annual activities of the sun for a long time,because they ignored the impact of the activities of the moon on the Earth’s climate change on a small scale,the 24 solar terms they summarized often could not accurately predict the change of the Earth’s climate.Therefore,the author studied the influence of lunar activities on the Earth’s climate change,finds out the law of the influence of lunar activities on the Earth’s climate change on a small scale,and summarizes the eternal climate change pattern determined by the activities of the sun and the moon.In addition,the author also reveals the causes and countermeasures of global warming and the frequent occurrence of extreme weather as well as environmental change.

Influence of the Tibetan Plateau on the Summer Climate Patterns over Asia in the IAP/LASG SAMIL Model

A series of numerical experiments are carried out by using the Spectral Atmospheric Model of State Key Laboratory of Numerical Modeling Atmospheric Sciences and Geophysical Fluid Dynamics/Institute of Atmospheric Physics （SAMIL） to investigate how the Tibetan Plateau （TP） mechanical and thermal forcing affect the circulation and climate patterns over subtropical Asia. It is shown that, compared to mechanical forcing, the thermal forcing of TP plays a dominant role in determining the large-scale circulation in summer. Both the sensible heating and the latent heating over TP tend to generate a surface cyclonic circulation and a gigantic anticyclonic circulation in the mid- and upper layers, whereas the direct effect of the latter is much more significant. Following a requirement of the time-mean quasi-geostrophic vorticity equation for large-scale air motion in the subtropics, convergent flow and vigorous ascending motion must appear to the east of TP. Hence the summer monsoon in East China is reinforced efficiently by TP. In contrast, the atmosphere to the west of TP is characterized by divergent flow and downward motion, which induces the arid climate in Mid-Asia.

δ13C-δ18O Covariance:An Effective Indicator of Hydrological Closure for Lakes?

The correlation between the δ^13C and δ^13C-δ^18O in primary carbonates is affected by several factors such as hydrological balance, total CO2 concentrations, climatic condition and lake productivity. The influence of these factors on the δ^13C-δ^18O correlation may be different on different time scales. In this paper, two different-type lakes in southwestern China, Lake Erhai and Lake Chenghai, are selected to investigate the influence of climatic pattern on the δ^13C-δ^18O correlation and to evaluate the reliability of the δ^13C-δ^18O covariance as an indicator of hydrological closure. The results show that there exists good correlation between the δ^13C and δ^18O in Lake Erhai （overflowing open lake） and in Lake Chenghai （closed lake）. This suggests that the δ^13C-δ^18O covariance may be not an effective indicator of hydrological closure for lakes, especially on short time scales. On the one hand, a hydrologically open lake may display covariant δ^13C and δ^18O as a result of climatic influence. The particular alternate warm-dry and cold-wet climatic pattern in southwestern China may be the principal cause of the δ^13C-δ^18O covariance in Lake Erhai and Lake Chenghai. On the other hand, a hydrologically closed lake unnecessarily displays covariant trends between δ^13C and δ^18O because of the buffering effect of high CO2 concentration on the δ^13C shift in hyper-alkaline lakes. We should be prudent when we use the covariance between δ^13C and δ^18O to judge the hydrological closure of lake.

Water Consumption of Seven Forage Cultivars under Different Climatic Conditions in the North China Plain

The objectives of this study were to determine the characteristics of water consumption of seven forage cultivars, ryegrass （Secale cereale L.）, triticale （×Triticosecale Wittmack）, sorghum hybrid sudangrass （Sorghum biolor× Sorghum Sudanense c.v.）, ensilage corn （Zea mays L.）, prince’s feather （Amaranthus paniculatus L.）, alfalfa （Medicago sativa L.）, and cup plant （Silphium perfoliatum L.）, in response to climate variability （especially precipitation）. Field experiments were conducted at Yucheng Integrated Experiment Station from 2005 to 2009. Fifteen irrigated lysimeters were used to measure evapotranspiration （ET） and crop coefficient （Kc） of these seven forage varieties under ample water supply. The mean Kc for alfalfa is 1.08, and the mean Kc for other forage varieties ranges from 0.79 to 0.94. Kc for hibernating forage is higher in wet years than that in dry years, followed by normal years, while for annual forage, Kc is higher in dry years than in normal years, and is the lowest in wet years. For perennial varieties the order is normal years, dry years, and wet years. Among the annual varieties, ensilage corn is the first choice due to its highest average forage N yield and water use efficiency （WUE）. Sorghum hybrid sudangrass is another forage cultivar that grows well under all climatic conditions. It can achieve 1.08-2.31 t ha-1 y-1 N yield under all circumstances. Prince’s feather is sensitive to climate change and its N yield dropped below half even when ample water was applied in dry and normal years. Ryegrass and triticale have the advantage of growing in the fallow phase after cotton is harvested in the North China Plain （NCP） and the latter performed better. For perennial varieties, alfalfa performed better than cup plant in dry years. With ample irrigation, alfalfa can achieve higher biomass and WUE under arid climate condition, but excessive rain caused reduction in production.

Circulation background of climate patterns in the past millennium: Uncertainty analysis and re-reconstruction of ENSO-like state

The question of whether or not global warming has paused since more than ten years ago, namely ＂warming hia- tus＂, has attracted the attention of climate science community including the IPCC. Some authors have attributed the ＂warming hiatus＂ to the internal changes in the climate system, i.e., the recombination of ocean-atmosphere circulations. Therefore, it is necessary to propose higher requirements on reconstructing circulation background of climate change for the past millennium. However, the analyses of changes in atmospheric circulation over the last millennium as well as the conclusions of related re- gional climate patterns are so widely different and contradictory, bringing uncertainties to our understanding of regional even global climate change to a great extent. On the other hand, in the last 10 years the high-precision U/Th-dated stalagmite oxygen isotope ratio （δ^18O） sequences provided an accurate chronological frame for the paleoclimate study of the middle and late Pleistocene, in which all authors from China took the Chinese stalagmite δ^18O as the summer monsoon index without excep- tion. However, this point of view misleads the climate scientists into thinking that the stalagmite δ^18O can be as the proxy of precipitation amount. Nevertheless, it is well known that all of these records have a lot in common in the low frequency trend. However, most sequences cannot be calibrated by instrumental precipitation records, and thus the uncertainty of the climate research framework of China and even of the world has increased. Therefore, it is imperative for climatology to clarify the origin of contradiction and to reduce the uncertainty as early as possible. On the basis of analyzing the significance of stalag- mite ~180 in the monsoon regions of China, the author tries to propose a new circulation proxy in this paper： integrating the Chinese stalagmite oxygen isotope sequence to reconstruct the tropical Pacific sea surface temperature gradient, i.e., the large-scale ENSO-like state over the past millennium. Furthermore, the author speculates that it was warm in the modern times and the Medieval Period, but the circulation recombination was different in both periods. And this inference could be support- ed by the longer record since Last Glacial Maximum. In other words, the attribution analysis of the identical low-frequency trends of Chinese stalagmite t^180 on a large scale shows that the ENSO-like state controls the climate change in the monsoon regions of China at different time scales （from interannual to century or even longer time scales）. Wherein the important connection of circulations is the western Pacific subtropical high （WPSH）, that is to say, besides the interannual and decadal time scales, the WPSH would possess the circulation mode on longer timescales. For example, we may discuss the change of the WPSH in the whole Holocene epoch, i.e., the half precession period. These discussions could make sense to the study of not only the paleoclimate but also the modern climate.

Current Progresses in Study of Impacts of the Tibetan Plateau on Asian Summer Climate

The current progresses in the study of impacts of the Tibetan Plateau on Asian summer climate in the last decade are reviewed. By analyzing evolution of the transitional zone between westerly to the north and easterly to the south （WEB）, it is shown that due to the strong heating over the Tibetan Plateau in spring, the overturning in the prevailing wind direction from easterly in winter to westerly in summer occurs firstly over the eastern Bay of Bengal （BOB）, accompanied with vigorous convective precipitation to its east. The area between eastern BOB and western Indo-China Peninsula thus becomes the area with the earliest onset of Asian monsoon, which may be referred as BOB monsoon in short. It is shown that the summertime circulations triggered by the thermal forcing of the Iranian Plateau and the Tibetan Plateau are embedded in phase with the continental-scale circulation forced by the diabatic heating over the Eurasian Continent. As a result, the East Asian summer monsoon is intensified and the drought climate over the western and central Asian areas is enhanced. Together with perturbations triggered by the Tibetan Plateau, the above scenarios and the associated heating have important influences on the climate patterns over Asia. Furthermore, the characteristics of the Tibetan mode of the summertime South Asian high are compared with those of Iranian mode. Results demonstrate that corresponding to each of the bimodality of the South Asian high, the rainfall anomaly distributions over Asia exhibit different patterns.

Eco-environmental changes in the Chinese Loess Plateau during low-eccentricity interglacial Marine Isotope Stage 19

Eco-environmental changes during interglacials with an astronomical background similar to that of the Holocene are potentially helpful for understanding the future climatic evolution.Marine oxygen isotope stage(MIS)19 is similar to the Holocene in astronomical background,both being characterized by a low eccentricity of the Earth’s orbit.However,MIS 19 has attracted research attention only recently and therefore less is known about eco-environmental changes during this interval,especially based on terrestrial records.In the Chinese Loess Plateau(CLP),the S7 paleosol can provide valuable terrestrial paleoclimatic and paleoenvironmental record for MIS 19.Here,high-resolution terrestrial snail records from the L8–L7 strata of the Huining,Xifeng and Luochuan sequences in the CLP were analyzed in order to characterize spatio-temporal changes in climate and eco-environment during MIS 20–18.The results show that in all three sections the late part of MIS 20 was dominated by abundant cold-aridiphilous mollusc species,indicating that cold and dry climatic conditions prevailed across the entire CLP,under the strong influence of the winter monsoon.The mollusc fauna of MIS 19 were dominated by warmth-loving and thermohumidiphilous species that enable the definition of two climatic stages.The early part of MIS 19(~790–778 ka)was marked by warm and humid conditions,as evidenced by high abundances of warmth-loving and thermo-humidiphilous species.This interval was slightly warmer than today and it lasted for^12 kyr.The climate of the later part of MIS 19(~778–761 ka)was more moderate,and increased proportions of cold-aridiphilous and warmth-loving species were recorded.The warmth of this period was similar to that of today,but the climatic fluctuations were stronger.During the early part of MIS 18(~761–745 ka),the Xifeng and Luochuan sections in the eastern CLP still maintained high abundances of warmth-loving and thermo-humidiphilous species,indicating that the moderate climatic conditions during late MIS 19 continued during early MIS 18,lasting for another^15 kyr,and that the influence of the summer monsoon remained strong in the eastern CLP during early MIS 18.However,in the western CLP,cold-aridiphilous species in the Huining section became dominant during early MIS 18,reflecting the prevalence of a cold and dry glacial climate,with the strong influence of the winter monsoon.These findings indicate that a steeper climatic gradient and a pronounced regional environmental difference existed between the eastern and western CLP during the early part of MIS 18.Comparison of our mollusc results with the variation of Earth orbital parameters suggested that climate changes in the CLP during MIS 20–18 were likely controlled mainly by insolation changes forced by the configuration of Earth orbital parameters.The unique orbital configuration during the low eccentricity interglacial-to-glacial transition could have strengthened the East Asian summer monsoon which favored the amelioration of the eco-environment in the CLP,especially in the eastern CLP where the summer monsoon exerted a strong influence.Thus we speculate that,under natural climatic conditions,the climate of the CLP may remain in a warm,humid state for another 30 kyr,although climatic instability and the seasonal differences between winter and summer could strengthen.