Estimation of urbanization bias in observed surface temperature change in China from 1980 to 2009 using satellite land-use data

Since the 1980s,China has undergone rapid urbanization.Meanwhile,the climate has been warming substantially.In this paper,the urbanization effect on observed temperatures from 1980 to 2009 in China is estimated,based on analysis of urban land use from satellite observation.Urban land-use expansion(U) during 1980-2005 is applied as an urbanization index.According to these U values,stations are divided into three categories:(C1) intense urbanization around the stations;(C2) moderate urbanization around the stations;and(C3) minimal urbanization around the stations.Most C1 stations are in municipalities or provincial capitals,while C2 stations tend to be in prefecture-level cities.C3 stations are mostly in counties.The urban heat island(UHI) effect can be estimated if the urban effect on C3 is negligible.The warming of C1 or C2 relative to that of C3 represents their urbanization effects,assuming that the same larger-scale natural warming has affected each category.For C1,the local urbanization effect is 0.258°C/10 a over 1980-2009,accounting for 41% of the total warming;the trend at C2 is 0.099°C/10 a,or 21%.For all China,the urbanization effect is 0.09°C/10a,accounting for 20% of the total national warming.Winter urban warming is greater than in summer.The assumption of negligible urbanization effect on C3 is debatable,and so the true urbanization effect may equal or slightly exceed estimates.Further,the U index may have some uncertainties,for it is only one of the urbanization indices.However,it provides a new and direct estimation of environmental change,in contrast to indirect indices.     

Meiyu in the middle and lower reaches of the Yangtze River since 1736

＂Yu Xue Fen Cun＂ records during the Qing Dynasty are used to identify the starting and ending dates of Meiyu at the period of 1736-1911. These results, along with the instrumental meteorological records, are used to reconstruct the series of length and precipitation of Meiyu during 1736-2000 over the middle and lower reaches of the Yangtze River. The characteristics of Meiyu are analyzed since 1736. Moreover, the strength of East Asian Summer Monsoon and locations of rainband are discussed, based on the relationship between the length of Meiyu and the Index of East Asian Summer Monsoon. It is found that the starting and ending dates and the length of Meiyu have significant interannual and interdecadal variations. Apart from 7-8 years, 20-30 years and 40 years cycles for the lengths of Meiyu, the centennial oscillation is also presented. The length of Meiyu, monsoon rainband movement over eastern China, and the strength of East Asian Summer Monsoon （EASM） have a very good correlation, which can be expressed in the following： during the periods of 1736-1770, 1821-1870 and 1921-1970, the EASM was stronger, and the monsoon rainband was located in North China and South China easily, corresponding to the decreased length of Meiyu. Whereas during the periods of 1771-1820, 1871-1920 and 1971-2000, the EASM was weaker and monsoon rainband usually stopped at the middle and lower reaches of the Yangtze River, corresponding to the increased length of Meiyu.     

Recombinant human PDCD5 protein enhances chemo-sensitivities of hematologic malignancies

PDCD5 is a novel apoptosis-related gene. Overexpression of PDCD5 facilitates apoptosis in various tumor cells. Here, we investigated the roles of recombinant human PDCD5 （rhPDCD5） protein in chemosensitivities of hematologic malignancies. The rhPDCD5 increased the in vitro cytotoxicity of daunorubicin （DNR）, adriamycin （ADM） and As203 in three hematologic tumor cell lines. In vivo studies showed that DNR combined with rhPDCD5 significantly suppressed tumor growth of U937 xenograft nude mice compared with DNR alone. In conclusion, rhPDCD5 combined with the chemotherapeutic drug has greater efficacy than chemotherapy alone, and rhPDCD5 is a very promising chemosensitizer.     

Modern pollen-vegetation relationship based on discriminant analysis across an altitudinal transect on Gongga Mountain, eastern Tibetan Plateau

Quantitative relationship between modern pollen assemblage and altitudinal vegetation belt is crucial for the reconstruction of paleovegetation in the mountain regions.Modern pollen analysis on 70 topsoil samples was conducted across an altitudinal transect(1100-4500 m) on the eastern slope of Gongga Mountain in the eastern Tibetan Plateau with an elevation interval of 50 m.Distributions of major pollen types along the transect indicated a weak correlation between Pinus pollen and the elevation.Distributions of Picea and Abies pollen(percentage sum of 2%-8%) could fairly indicate the elevation range of 2700-3700 m,as well as the subalpine dark coniferous forest and the timberline in the region.High percentage intervals of alpine types of Ericaceae,Cupressaceae and Cyperaceae were correlated to the high-elevation regions(3700-4500 m) dominated by alpine shrub meadow and alpine meadow.Seven altitudinal vegetation belts on the eastern slope of Gongga Mountain were well defined by discriminant analysis conducted on the modern pollen assemblages,as reflected by high values of probability of modern analog.Most of the modern pollen assemblages(88.5%) were typical for the vegetation types at their sampling locations.Thus,the relationship between the modern pollen assemblages and vegetation across the altitudinal transect based on discriminant analysis can be applied to the quantitative reconstruction of paleovegetation changes in the mountain regions of the eastern Tibetan Plateau.     

Societal response to challenges of global change and human sustainable development

It is now widely accepted that carbon emission from human activities is an important driving force in global warming, and global change has a deep impact on sustainable development of human society. To meet the challenges of global change, the international community has reached a consensus that developed countries take strict actions in emission reduction, whereas developing countries take spontaneous efforts in reducing emissions under the guiding principle of common but differentiated responsibilities, with an agreed goal to restrict global surface temperature increase due to human activities to within 2℃ of pre-industrial levels. However, there is no clear pathway to reach this goal. A number of related questions must be addressed on principles to be followed, research emphasis and policy measures. Here we argue that response policies to address global change issues must be based on balanced development at regional and international levels, and on advancements in science and technology. This requires consideration of harmony not only between humans and nature but also within human societies, to properly deal with the relationship between global change and sustainable development. We must make equal efforts toward carbon emission reduction and carbon sequestration, and toward mitigation and adaptation. There should be more research support to reduce uncertainties in our understanding of global change. Addressing the challenges of global change creates great opportunities for the development of human society. This will facilitate transformation of energy use structure, improve and restore ecological functioning of the earth environment, transform production modes and ways of living in human society, and promote harmonic and balanced development at regional and international levels.     

Reconstructing temperature change in Central East China during 601–920 AD

Using historical records on first and last frost and snow, spring cultivation, David peach blossom, autumn crop harvest, grade of sea freeze and change in northern citrus boundary, we reconstructed temperature change during 601–920 AD. The mean temperature of the winter half-year (October to April) over Central East China during this period was about −0.22°C higher than that of the present (1961–2000 AD mean). During 601–820 AD, mean temperature was about −0.52°C higher than the present. During 821–920 AD, the mean temperature was 0.42°C lower than the present. The temperature fluctuations were characterized by a maximum amplitude of 1.05°C at the centennial scale, 1.38°C at the 50–year scale, 2.02°C at the 30-year scale, and 2.3°C at the 20-year scale. There were four peaks warmer than today (601–620 AD, mean of 1°C higher temperature; 641–660 AD, 1.44°C; 701–720 AD, 0.88°C; 781–800 AD, 0.65°C). Three cold periods were in 741–760, 821–840, and 881–900 AD, the mean temperature of which was 0.37–0.87°C lower than the present.     

Experimental study on burning rate of small scale heptane pool fires

Burning characteristics of small scale thin-layer n-heptane pool fires were experimentally studied.Flame height,burning rate and fuel temperature distribution of pool fires with different diameters were measured.Fuel surface temperature and wall heat flux were analyzed.Four typical burning phases,which include pre-burning,quasi-steady state burning,boiling burning and decaying phases,are revealed based on the experimental data and phenomenological analysis.It is shown that flame height and burning rate of b...