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1.
The Chilean Lake District (38–42°S) is strongly influenced by Southern westerlies-driven precipitations. At 40°S Lago Puyehue provides high resolution sedimentation rates (∼1–2 mm/yr) suitable for annual climate reconstruction. Several short and long sediment cores were collected in this lake. Their analysis aim at a better understanding of climate mechanisms related to ENSO in this part of the world. The recognition of ENSO related periodicities and their stability is studied through the analysis of two short varved cores collected from underflow and interflow key sites. According to varve chronology controlled by 137Cs and 210Pb profiles and chronostratigraphical markers, the short core from underflow site (PU-I) spans 294 ± 18 years and the core in the interflow site (PU-II) covers 592 ± 9 years. Several methods of spectral analysis were applied on the total varve thickness to identify potential periodicities in the signal. Blackman–Tuckey, Maximum Entropy, Multi-Taper Methods (MTM) and singular spectrum analysis were applied on the whole record. In addition, evolutive MTM and wavelet analyses allow to identify temporal influence of some periodicities. In the PU-I studied interval (AD 1700–2000), a period at ∼3.0 years appears in a large part of the interval, mostly in the recent part. Periods at ∼5.2 and ∼23 years also show up. PU-II record (AD 1400–2000) displays the most robust periodicities at around 15, 9, 4.4, 3.2 and 2.4 years. These periodicities are in good agreement with the sub-decadal periods identified by Dean and Kemp (2004) and linked to the El Nino Southern Oscillation and the Pacific Decadal Oscillation. Differences in the recorded periodicities between PU-I and PU-II sites are consistent with different sedimentation processes in the lake. According to climate instrumental data for the last 20 years, varves in PU-I site are mostly related to fluvial dynamics and regional climate factors, i.e., precipitation, temperature and wind. In PU-II site, varves increment is related to both regional and global climate forcing factors, i.e., El Nino Southern Oscillation. The evolutive MTM analysis and the wavelet analysis suggest a striking break in the periodicities at around AD 1820. Finally relationships between El Nino and longer term climate phase like the Little Ice Age (LIA) are also assessed. This is the seventh in a series of eight papers published in this special issue dedicated to the 17,900 year multi-proxy lacustrine record of Lago Puyehue, Chilean Lake District. The papers in this special issue were collected by M. De Batist, N. Fagel, M.-F. Loutre and E. Chapron.  相似文献   

2.
Microlaminated sediment cores from the Kalya slope region of Lake Tanganyika provide a near-annually resolved paleoclimate record between ∼∼2,840 and 1,420 cal. yr B.P. demonstrating strong linkages between climate variability and lacustrine productivity. Laminae couplets comprise dark, terrigenous-dominated half couplets, interpreted as low density underflows deposited from riverine sources during the rainy season, alternating with light, planktonic diatomaceous ooze, with little terrigenous component, interpreted as windy/dry season deposits. Laminated portions of the studied cores consist of conspicuous dark and light colored bundles of laminae couplets. Light and dark bundles alternate at decadal time scales. Within dark bundles, both light and dark half couplets are significantly thinner than within light bundles, implying slower sediment accumulation rates during both seasons over those intervals.Time series analyses of laminae thickness patterns demonstrate significant periodicities at interannual–centennial time scales. Longer time scale periodicities (multidecadal to centennial scale) of light and dark half couplet thicknesses are coherent and in some cases are similar to solar cycle periods on these time scales. Although laminae thickness cycles do not strongly covary with the actual Δ14C record for this same time period, two large Δ14C anomalies are associated with substantial decreases in both light and dark laminae thickness. In contrast to the multidecadal– centennial time scale, significant annual to decadal periodicities, which are broadly consistent with ENSO/PDO forcing and their impact on East African climate, are not coherent between light and dark half couplets. The coherency of light–dark couplets at decadal–centennial time scales, but not at shorter time scales, is consistent with a model of a long-term relationship between precipitation (recorded in wet season dark laminae thickness) and productivity (light laminae thickness), which is not manifest at shorter time scales. We hypothesize that this coupling results from long-term recharging of internal nutrient loading during wet periods (higher erosion of soil P) and reduced loading during drought intervals. The relationship is not expressed on short time scales during which the dominant control on productivity is wind-driven, dry season upwelling, which is uncorrelated with wet-season precipitation. Our record greatly extends the temporal record of this quasi-periodic behavior throughout the late Holocene and provides the first evidence linking decade- to century-scale episodes of enhanced productivity to enhanced precipitation levels and nutrient recharge in a productive tropical lake.  相似文献   

3.
Accurate determination of the thicknesses of 2717 biogenic carbonate varves from a Swiss lake (Soppensee), spanning the period from about 9740 to 6870 calendar yr BP, allowed the computation of a power spectrum using classical FFT methods. The presence of pronounced peaks at 40-50 and 20-25 yr agrees with the results of other studies on varve thickness and D14C which have been interpreted as indicating an association between solar forcing and varve thickness. The presence in the Soppensee varve series of an additional peak at 10.9 yr, corresponding to the Schwabe sunspot cycle, lends further support to this hypothesis. Because the Soppensee varves are of biogenic rather than clastic origin, any influence fluctuations in solar irradiance may have had on sedimentation rates is likely to have been exerted via primary production.  相似文献   

4.
This study assesses Little Ice Age (LIA) lake sediment morphological and geochemical records and moraine chronologies in the upper Fraser River watershed, British Columbia, Canada, to resolve differences in paleoenvironmental interpretation and to clarify sediment production and sediment delivery processes within alpine geomorphic systems. Moose Lake (13.9 km2), situated at 1032 m a.s.l., contains a partially varved record indicating variable rates of accumulation during the last millennium that, in general, coincide with previously documented LIA glacial advances in the region and locally. Dendrochronological assessment of forefield surfaces in the headwaters of the catchment (Reef Icefield) shows that periods of moraine construction occurred just prior to ad 1770, ad 1839 and ad 1883, and some time before ad 1570. Taken collectively, increases in varve thickness within eight Moose Lake sediment cores coincide with documented glacier advances over the twelfth through fourteenth centuries, the eighteenth century, and nineteenth through twentieth centuries. Glacial activity during the sixteenth century is also indicated. While varve thickness variations in proximal and distal sediments clearly reflect glacial activity upstream of Moose Lake, the intermediate varve record is relatively insensitive to these decadal and longer‐term catchment processes. Variations in Ca and related elements derived from glaciated carbonate terrain within the Moose River sub‐catchment (including Reef Icefield) indicate gradually increasing delivery from these sources from the twelfth through twentieth centuries even where the varve thickness record is unresponsive. Elevated carbonate concentrations confirm glacial activity c. ad 1200, ad 1500, ad 1750, and ad 1900.  相似文献   

5.
利用1999—2011年EISCAT(EISCAT Tromsø UHF)和ESR(EISCAT Svalbard Radar)雷达的场向电子密度观测数据, 对比分析了两处雷达观测到的极区E层占优电离层ELDI (E-Layer Dominated Ionosphere)事件在太阳活动高、低年的统计特征。地面雷达观测表明, 太阳活动水平对极区ELDI发生率的空间分布影响显著: 在太阳活动高年, ELDI在EISCAT雷达处(极光椭圆区纬度)的发生率高于ESR雷达处(极尖/极隙区纬度); 在低年则恰好相反。夏季似乎不利于ELDI的发生, 且在该季节的变化特征不受太阳活动水平及空间位置变化的影响。两部雷达在太阳活动高年观测到ELDI的季节变化规律分别与低年期间的结果相一致: 在冬季和早春, ELDI的发生率较高, 其他季节发生率较低, 夏季尤其低。在ELDI事件期间, 两处雷达观测到事件的持续时间和电离层E层厚度随太阳活动水平的变化表现出明显差异: 高年事件的持续时间总体上比低年短, 低年观测到ELDI的厚度要小于高年结果; 然而NmE/NmF2比值及HmE却没有表现出明显依赖。  相似文献   

6.
《自然地理学》2013,34(2):144-184
Soon (2005) showed that the variable total solar irradiance (TSI) could explain, rather surprisingly, well over 75% of the variance for the decadally smoothed Arctic-wide surface air temperature over the past 130 years. The present paper provides additional empirical evidence for this physical connection, both through several newly published high-resolution paleo-proxy records and through robust climate-process modeling outputs. This paper proposes a mechanistic explanation, involving: (1) the variable strength of the Atlantic meridional overturning circulation (MOC) or thermohaline circulation (THC); (2) the shift and modulation of the Inter-Tropical Convergence Zone (ITCZ) rainbelt and tropical Atlantic ocean conditions; and (3) the intensity of the wind-driven subtropical and subpolar gyre circulation, across both the North Atlantic and North Pacific. A unique test of this proposed solar TSI-Arctic thermal-salinity-cryospheric coupling mechanism is the 5- to 20-year delay effect on the peak Atlantic MOC flow rate centered near 30-35°N, and on sea surface temperature (SST) for the tropical Atlantic. The solar Arctic-mediated climate mechanism on multidecadal to centennial timescales presented here can be compared with and differentiated from both the related solar TSI and UV irradiance forcing on decadal timescales. The ultimate goal of this research is to gain sufficient mechanistic details so that the proposed solar-Arctic climate connection on multidecadal to centennial timescales can be confirmed or falsified. A further incentive is to expand this physical connection to longer, millennial-scale variability as motivated by the multiscale climate interactions shown by Braun et al. (2005), Weng (2005), and Dima and Lohmann (2009).  相似文献   

7.
Image analysis as a method to quantify sediment components   总被引：1，自引：0，他引：1  
Varved lake sediments, with their annual to seasonal resolution, have a high potential for inferring past environmental and climatic conditions. To fully utilize the information present in varved records, high-resolution analyses, which often are time-consuming and difficult to perform, are desirable. The investigation reported here aims at (i) developing image analysis as a method for estimating annual accumulation rates of sediment components such as minerogenic matter, organic matter and biogenic silica, and (ii) assessing the relative importance of these components for changes in varve thickness. Image analysis was used to digitize the grey-scale variations and to measure the varve thickness of 540 varves (476-1015 AD) from Lake Kassjön in northern Sweden. From the 35 cm long digitized sediment sequence, 108 consecutive five-year samples were cut out quantitatively, and relationships between grey-scale variations and sediment dry mass and individual sediment components were assessed. There is a strong correlation between corrected grey-scale (i.e. the product of grey-scale and varve thickness) and the dry mass accumulation rate (r = 0.90, p < 0.001). With a stepwise multiple regression a significant model (R2 = 0.81) between corrected grey-scale and the accumulation rates of minerogenic matter (r = 0.90, p < 0.001) and biogenic silica (r 0.26, p < 0.012) was obtained. Considering the minor contribution and weak significance of biogenic silica, image analysis can be used as a fast and non-destructive method to infer past annual accumulation rates of dry mass and minerogenic matter in Kassibn. The model of the relationship between changes in varve thickness, and water content and accumulation rates of sediment components has little predictive power (R2 = 0.45). The result shows that the varve thickness in Kassjön, at least during the period 476-1015 AD, is not determined by a single sediment component but partly depends on interactions between the major sediment components.  相似文献   

8.
Two varve counts made nearly 20 yrs apart and by different authors in the small and well sheltered meromictic lake of Valkiajärvi were compared with a view to establishing how similar, or otherwise, these two independent varve chronologies might be. The results were significant, the difference between the two varve counts being less than 2% for most of the sediment length, even though the average varve thickness was only 0.3 mm. The continuous and essentially uniform varve record - so far the longest in Finland - covers 8400 yrs and could be applied for accurate dating of palaeoenvironmental indicators in the sediment. As an example, we present a varve-dated pollen diagram for Lake Valkiajärvi.In addition, some magnetic parameters (susceptibility, ARM, SIRM) were measured on the sediment sequence to support the stratigraphic division and correlation of the cores, and to outline the development of the basin since the last deglaciation. Magnetic variables reflected mainly the variation in minerogenic material in the sediment, and were therefore related to changes in the catchment. The magnetic parameters also showed a drastic change some 6000 yrs ago, the reason for which, unfortunately, is still not fully understood.  相似文献   

9.
In this paper, the relationships between paleo-precipitation and the regional influence of El Nino Southern Oscillation (ENSO) in South America are assessed from a high-resolution calendar varve-thickness record. Two short laminated sediment cores (53 and 61 cm length) from Lago Puyehue (40° S) are analysed by continuous varve measurements through the last 600 years. The calendar varve years are determined by the occurrence of graded planktonic-rich layers. The annual sediment accumulation rates are reconstructed by using the standard varve-counting methods on thin sections. The 1980–2000 varve-thickness record is interpreted in terms of climate through correlation with limnological and local monthly instrumental climate databases. The comparison between the standardized varve thickness with the instrumental records reveals a strong correlation (r = 0.75, р = 0.07) between the total varve thickness and the austral autumn/winter precipitation. We argue that strong austral winter winds and precipitation are the forcing factors for the seasonal turn-over and phytoplankton increase in the lake sediments. During strong El Nino events the precipitation and the winds decrease abnormally, hence reducing the thickness of the biogenic sediments deposited after the winter turn-over. Our results show one significant regional maximum peak of winter precipitation (>900 mm) in the mid 20th century and a significant period with lower winter precipitation (<400 mm) before the 15th century, i.e., the late Medieval Warm Period. The first peak in the mid 20th century is confirmed by the regional precipitation database. The influence of ENSO cycles over the last 600 years is assessed by spectral analysis in Fagel et al. (2007). The possible influence of the regional volcanism and/or the seismic activity on the local climate record is also discussed. This is the sixth in a series of eight papers published in this special issue dedicated to the 17,900 year multi-proxy lacustrine record of Lago Puyehue, Chilean Lake District. The papers in this special issue were collected by M. De Batist, N. Fagel, M. -F. Loutre and E. Chapron.  相似文献   

10.
The sediments from Lake Bosumtwi, Ghana contain a unique record of fine-scale (mm to sub-mm) laminations, which will provide a valuable annual chronometer for reconstructing paleoenvironmental changes in West Africa covering much of the last 1 Ma. Comparisons of laminae counts to independent 210Pb dates and the rise in anthropogenic “bomb” radiocarbon support the interpretation of the laminations in the uppermost sediments as registering annual events. Radiocarbon dates on in-situ fish-bone collagen are in agreement with varve counts, further supporting the annual nature of our varve chronology. Over the instrumental period (1925–1999), dark-varve thickness measurements are correlated with local rainfall (r = 0.54) and appear able to resolve decadal-scale changes in precipitation. The relationship between varve thickness and rainfall provides support for our interpretation that dark-colored varve thickness records catchment runoff during the rainy season rather than dust flux during the dry season. Dark laminae alternate with organic and carbonate-rich light laminae formed during the fall period of enhanced productivity. Downcore, varves undergo significant microstratigraphic and geochemical variations, but retain the same pattern of alternating clastic and organic-rich laminae, providing support that the laminae may represent annual time markers for reconstructions of the deeper part of the record.  相似文献   

11.
清代泾河中游地区洪涝灾害研究   总被引：8，自引：5，他引：3  
频谱分析发现泾河中游地区洪水发生具有周期性,比较显著的周期有101年、11年、3.4~2.2年周期等,其中101年和11年周期可以和太阳活动的周期相对应,3.4~2.2年周期则可能与热带海气耦合规律有关,说明太阳活动和低纬海洋大气活动对该地区洪涝灾害都有影响。每个世纪中期是该地区洪涝灾害较为集中的时期。  相似文献   

12.
李净  王丹  冯姣姣 《地理科学》2017,37(6):912-919
现有的神经网络模拟太阳辐射的模型很少考虑云、气溶胶、水汽对太阳辐射的影响,采用MODIS提供的气溶胶、云、水汽高空大气遥感产品和常规气象数据,输入LM（Levenberg-Marquardt）算法优化后的BP（Back-Propagation）神经网络模型（简称LM-BP）模拟了和田、西宁、固原、延安4个辐射站点的太阳辐射月均值。验证结果表明：神经网络模型中加入气溶胶、云、水汽之后,4个辐射站点的R2均大于0.90,且各项误差指标均小于仅用常规气象站点数据模拟的太阳辐射结果。  相似文献   

13.
Statistical analysis of a multi-centennial dendrochronological proxy dataset of regional climate, constructed across the latitudinal gradient of 1000 km, was performed. It was shown that centennial ( c. 100 year), tri-decadal (27-32 year), bi-decadal (17-23 year) and decadal (9-13 year) periodicities governed the climate variability in Finland over the last five centuries. Despite the fact that many of the climatic periodicities bore great resemblance to periodicities of solar cycles, little evidence of actual solar influence on Finnish climate was found when the climate proxy records were subjected to linear correlation analysis with sunspot numbers. Highly non-linear response of Northern Fennoscandian climate to solar forcing might be a cause of this result, as well as influence of terrestrial climatic processes (e.g. effect of other forcing factors and internal dynamics of regional climate). Our results show that the presence of internal climate variability at time-scales of solar activity might distort the solar signature in climatic data and complicate its detection.  相似文献   

14.
Remanence directions, measured at 2  cm intervals along a composite 88  m bore-core, enable mean palaeomagnetic poles to be defined at 13.6°S, 25.2°W and 13.6°N, 154.8°E. The directions of remanence vary very smoothly away from each palaeomagnetic pole, extending more than 90° from them. This raises doubts about the physical meaning of polarity definitions based on the distance between virtual and mean palaeomagnetic poles. For practical purposes, intermediate polarity is defined as directions whose virtual poles lie more than 25° from the mean pole, enabling at least five normal subchrons to be specified within the upper predominately reversed quarter of the core and 11 reversed subchrons within the lower predominantly normal three-quarters of the core. The stratigraphic thickness between these subchrons shows a very high linear correlation ( r >0.99) with the stratigraphic thickness of other terrestrial sequences and the distances between marine polarity sequences of comparable age. The analysed sequence contains wavelength spectra which, when transformed to the temporal realm, match periodicities determined for three marine magnetic anomaly profiles of similar age. These also match planetary orbital periodicities for the Cretaceous. These observations suggest that secular variations and polarity transitions are driven by common core processes whose surface expression is influenced by changes in the planetary orbits. Such detailed geomagnetic features enable far greater reliability in establishing magnetostratigraphic correlations and also enable them to be dated astronomically.  相似文献   

15.
A 95-cm-thick peat sequence obtained from Daping Swamp in the western Nanling Mountains provides evidence for climate variability in the past ~3,000 year. Multi-proxy records (including organic carbon isotopes, humification degree, organic matter content, and dry bulk density) revealed three intensified Asian summer monsoon (ASM) intervals (i.e.~2900–2700, 2500–1700 and 1000–600 cal. yr BP) and three weakened ASM intervals (i.e.~2800–2500, 1700–1000 and 600–200 cal. yr BP). Our δ13C record shows a possible correlation with the sunspot number and residual atmospheric 14C records on multi-centennial scale, especially for the period between 2960 and 2200 cal. yr BP. A spectral analysis of δ13C record reveals three significant cycles (i.e., 396, 110 and 102 yr) and all these cycles could be related to solar activity, suggesting that solar output may have influenced the late Holocene climate variability in the study region.  相似文献   

16.
A comparison is made of the calculated values of solar radiation incident on the upper atmospheric boundary with the measured values of surface temperature on the territory of the Crimean Peninsula. It is shown that the long-term temperature regime on the territory of the Crimean Peninsula is characterized by a stability. It is determined that the stability of the long-term regime of mean annual surface air temperatures is associated with the characteristics of the latitudinal distribution of solar radiation incident on the upper atmospheric boundary. The incident solar radiation increases in the regions of heat sources and decreases in the regions of heat sink. Stability of long-term mean annual values of surface air temperature is associated with the location of the Crimea on the boundary of the regions of heat sources and sinks. The study revealed the chronological structure of long-term changes in surface air temperature. The anomaly in the long-term surface air temperature variability is characterized by short-duration variations. An analysis is made of the chronological structure of interannual variability in surface air temperature on the territory of the peninsula. The dominant interannual and 2–3-year periodicities in the temperature regime variations are correlated with variations in incident solar radiation. In 62.7% of cases, the sign of interannual variability in surface air temperature corresponds to the sign of interannual variability in incident solar radiation. Thus it is shown that a small tendency in the long-term surface air temperature variability on the territory of the Crimean Peninsula, and the characteristics of its variations are determined largely by the specific character of the input and distribution of solar radiation incident on the upper atmospheric boundary.  相似文献   

17.
饶俊峰  张显峰 《热带地理》2015,35(6):852-859
以香港地面站观测的AOD与WVC数据为参照,首先分析了MISR/AOD和MODIS/WVC产品的不确定性描述方法,然后在考虑二者联合不确定性的影响下,推导了辐射传输方程法估算地面太阳短波辐射的相对误差分布函数。通过统计2005―2013年香港MISR/AOD和MODIS/WVC反演值的分布情况,得出两者的联合概率密度函数,然后将AOD和WVC的联合概率密度函数作为权重函数与相对误差分布函数积分,得到对辐射传输方程法估算地面太阳短波辐射的相对误差数学期望。结果表明,夏季在太阳天顶角为0°时,使用MISR/AOD和MODIS/WVC产品估算地面太阳短波辐射的相对误差期望为3.17%,并且有90%的把握使估算结果相对误差＜3.53%;不同季节不同太阳天顶角下、不同置信水平下,地面太阳短波辐射估算的相对误差大小,可为不同应用研究提供基础数据,为评估亚热带地面太阳短波辐射估算结果是否符合应用需求提供依据。  相似文献   

18.
青海沙利克山祁连圆柏千年树轮宽度序列的变化特征   总被引：6，自引：1，他引：5  
利用功率谱、奇异谱和小波分析等方法对在青海沙利克山建立的两条祁连圆柏 (Sabi naprzewalskiiKom )千年树轮宽度序列进行了变化特征的分析 ,发现在低频变化上都存在2 0 0年的最显著周期和百年左右的显著周期 ;各种周期存在不同的演变特征 ,2 0 0年周期在15～ 17世纪最为盛行 ,百年左右的周期变化自 18世纪初以来较为突出。 15世纪下半叶是轮宽序列千年来最突出的低值期 ,它主要体现了 2 0 0年周期的变化 ,而 2 0世纪后期的高值区则主要是百年左右周期变化的作用。轮宽序列的低频变化与太阳活动的长期变化之间存在较好的对应关系 ,说明祁连圆柏年轮宽度序列所指示的气候低频变化可能受太阳活动的影响。  相似文献   

19.
Sediments from a 3 ha lake (75 °34.34N, 89 °18.55W) from the coastal region of northern Devon Island, Nunavut, Canada, contain discrete laminations in the deepest part of the basin. The laminations are varves as indicated by the correspondence between counts and thickness measurements of the couplets and 210Pb dating. A 14 cm core representing 150 years of sedimentation contained laminated couplets consisting of a lighter inorganic layer with a higher percentage of calcium and magnesium, alternating with fine darker bands, typically more cohesive, and comprising higher proportions of silica and carbon. A reddish oxidation zone with higher iron and aluminum frequently separates the laminations. The dark layer represents a biogenic component deposited in summer and is made cohesive by bacterial filaments among the other particles. The light inorganic layer represents clastic deposition from allochthonous sources. Deposition rates were relatively consistent through the core with an increase in varve thickness in the 1950s. Diatom concentrations in the sediments increased by two orders of magnitude in this century, with major increases in the 1920s and 1950s. The increase in varve thickness and diatom abundance coincides with an increase in summer melt percentage in an ice core from the Devon Island Ice Cap (Koerner, 1977). The relatively high sedimentation rate (0.15 cm yr-1) coupled with the consistency of deposition makes this lake a significant indicator for recent climate changes of the Canadian Arctic Archipelago.  相似文献   

20.
根据1993—2016年昆明市24 a太阳辐射及其他相关资料,采用回归分析、Mann-Kendall突变检验、小波分析和灰色关联度等方法,分析昆明市地面太阳辐射变化特征,并对其影响因子进行了分析。结果表明,近24 a来昆明市地面接收年太阳辐射量在4620.21~6221.65 MJ/m 2之间变化,最大值出现在2016年,最小值出现在2008年,平均每年的太阳辐射为5598.06 MJ/m 2,且整体上呈现波动式上升趋势。昆明市干湿季分明,干季(11月—次年4月)地面得到的太阳辐射量较多,为2825.22 MJ/m 2,雨季(5—10月)较少,为2774.41 MJ/m 2;一年中地面接收太阳辐射量最多月份在4月,其值为604.75 MJ/m 2,最少的是12月,其值为361.01 MJ/m 2,相差243.74 MJ/m 2。地面接收的太阳辐射有一个突变点为2014年,但不明显。年小波分析表明,近24 a昆明市各年地面接收的太阳辐射量主周期为15 a;季节小波分析发现,干季比雨季振幅大,其主周期都为19 d。近24 a昆明市地面太阳辐射受自然和人为因子共同影响,其中自然因子对太阳辐射影响最大的是降水量,人为因子中对太阳辐射影响最大的是工业总产值,且自然因子的作用大于人为因子。  相似文献   

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