scholarly journals THE REGIONAL DIFFERENCES OF GPP ESTIMATION BY SOLAR INDUCED FLUORESCENCE

2018 ◽  
Vol XLII-3 ◽  
pp. 1805-1807
Author(s):  
X. Wang ◽  
S. Lu
Keyword(s):  
Global Climate ◽  
Spatial Scales ◽  
Linear Regression Analysis ◽  
Total Precipitation ◽  
Annual Average ◽  
Average Temperature ◽  
Annual Total Precipitation ◽  
Annual Total ◽  
The Relationship ◽  
Annual Average Temperature

Estimating gross primary productivity (GPP) at large spatial scales is important for studying the global carbon cycle and global climate change. In this study, the relationship between solar-induced chlorophyll fluorescence (SIF) and GPP is analysed in different levels of annual average temperature and annual total precipitation respectively using simple linear regression analysis. The results showed high correlation between SIF and GPP, when the area satisfied annual average temperature in the range of −5 °C to 15 °C and the annual total precipitation is higher than 200 mm. These results can provide a basis for future estimation of GPP research.

Variations of Temperature in Hefei City in Recent 50 Years

2012 ◽  
Vol 616-618 ◽  
pp. 1496-1499
Author(s):  
Guo Wei Xu ◽  
Xin Tian Yuan ◽  
Shu Ling Huang ◽  
Yang Gao
Keyword(s):  
Statistical Analysis ◽  
Temperature Increase ◽  
Summer Temperature ◽  
Observation Data ◽  
Annual Average ◽  
Average Temperature ◽  
Four Seasons ◽  
Temperature Observation ◽  
Significant Temperature ◽  
Annual Average Temperature

Selecting 50 years temperature observation data from1959 to 2008 and using statistical analysis, this paper revealed the characteristics of temperature variation in Hefei city. The results show that in past 50 years, the annual average temperature in Hefei city greatly increased, tendency rate of temperature change was 0.246°C/10 a, especially after 1993, the temperature increased significantly; the temperature in four seasons all increased somewhat, warming was most prominent in spring. The most significant temperature increase was in spring, winter following behind, temperature increase in autumn was not obvious, and the average summer temperature increased the most unobvious.

scholarly journals Historical Spatial and Temporal Climate Trends in Southern Ontario, Canada

2017 ◽  
Vol 56 (10) ◽  
pp. 2767-2787 ◽  
Author(s):  
Hussein Wazneh ◽  
M. Altaf Arain ◽  
Paulin Coulibaly
Keyword(s):  
Climate Models ◽  
Global Climate ◽  
Global Climate Models ◽  
Climate Indices ◽  
Total Precipitation ◽  
Southern Ontario ◽  
Temperature And Precipitation ◽  
Annual Total ◽  
Precipitation Indices ◽  
Temperature Indices

AbstractSpatial and temporal trends in historical temperature and precipitation extreme events were evaluated for southern Ontario, Canada. A number of climate indices were computed using observed and regional and global climate datasets for the area of study over the 1951–2013 period. A decrease in the frequency of cold temperature extremes and an increase in the frequency of warm temperature extremes was observed in the region. Overall, the numbers of extremely cold days decreased and hot nights increased. Nighttime warming was greater than daytime warming. The annual total precipitation and the frequency of extreme precipitation also increased. Spatially, for the precipitation indices, no significant trends were observed for annual total precipitation and extremely wet days in the southwest and the central part of Ontario. For temperature indices, cool days and warm night have significant trends in more than 90% of the study area. In general, the spatial variability of precipitation indices is much higher than that of temperature indices. In terms of comparisons between observed and simulated data, results showed large differences for both temperature and precipitation indices. For this region, the regional climate model was able to reproduce historical observed trends in climate indices very well as compared with global climate models. The statistical bias-correction method generally improved the ability of the global climate models to accurately simulate observed trends in climate indices.

scholarly journals Numerical simulation of formation and preservation of Ningwu ice cave, Shanxi, China

2015 ◽  
Vol 9 (2) ◽  
pp. 2367-2395 ◽  
Author(s):  
S. Yang ◽  
Y. Shi
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Process ◽  
Shanxi Province ◽  
Mechanism Of Formation ◽  
Annual Average ◽  
Average Temperature ◽  
Control Factors ◽  
Tourism Resource ◽  
Ice Water ◽  
Annual Average Temperature

Abstract. Ice caves exist in locations where annual average temperature in higher than 0 °C. An example is Ningwu ice cave, Shanxi Province, the largest ice cave in China. In order to quantitatively explain the mechanism of formation and preservation of the ice cave, we use Finite Element Method to simulate the heat transfer process at this ice cave. There are two major control factors. First, there is the seasonal asymmetric heat transfer. Heat is transferred into the ice cave from outside, very inefficiently by conduction in spring, summer and fall. In winter, thermal convection occurs that transfers heat very efficiently out of the ice cave, thus cooling it down. Secondly, ice–water phase change provides a heat barrier for heat transfer into the cave in summer. The calculation also helps to evaluate effects of global warming, tourists, etc. for sustainable development of ice cave as tourism resource. In some other ice caves in China, managers installed air-tight doors at these ice caves entrance intending to "protect" these caves, but this prevent cooling down these caves in winters and these cave ices will entirely melt within tens of years.

The Coincident Relationships between the Qehan Lake Area Fluctuation and the Climate Change in the Nearly 40 Years

2011 ◽  
Vol 137 ◽  
pp. 286-290 ◽  
Author(s):  
Xi Chun ◽  
Mei Jie Zhang ◽  
Mei Ping Liu
Keyword(s):  
Climate Change ◽  
Inner Mongolia ◽  
Climatic Factors ◽  
Annual Precipitation ◽  
Lake Area ◽  
Annual Average ◽  
Average Temperature ◽  
Changing Patterns ◽  
Annual Evaporation ◽  
Annual Average Temperature

The objective of this study is to analyse the climate changing patterns chronologically for exposing the coincident relationships between the lake area fluctuation and the climate change in Qehan lake of Abaga county of Inner Mongolia. The results show that there’s highly interrelation between the changes of the lake area and the climatic factors here, the annual average temperature and annual evaporation are negatively interrelate to the lake area fluctuation, and the annual precipitation interrelate to it is positive. The lake area has descended about 75 km2 during the nearly past 40 years. There were about two considerable lake expansions in 1973, 1998 through the generally lake area descending process.

The Relationship between Energy Consumption and Climate Change in Shanghai

2012 ◽  
Vol 524-527 ◽  
pp. 2388-2393 ◽  
Author(s):  
Nan Wang ◽  
Mahjoub Elnimeiri
Keyword(s):  
Climate Change ◽  
Energy Consumption ◽  
Energy Use ◽  
Fossil Fuel ◽  
Average Temperature ◽  
The Past ◽  
Strong Positive Relationship ◽  
The Relationship ◽  
Annual Average Temperature ◽  
Fossil Fuel Energy

The phenomenon of climate change is becoming a global problem. One of the most important reasons of climate change is the increase in CO2 levels due to emissions from fossil fuel energy use in daily human activities. This research will use the data of the annual average temperature and energy consumption in the past 41 years of Shanghai, the largest city in China, to establish the statistical relationship between climate change and energy consumption. It is found that there is a strong positive relationship between climate change and energy consumption in Shanghai. The phenomenon of climate change could be controlled by reducing excessive energy consumption in people’s daily life. Furthermore, this paper will also discuss the reason of such relationship, and provide suggesstions of saving energy and protecting our environment.

scholarly journals Effects of solar activity and galactic cosmic ray cycles on the modulation of the annual average temperature at two sites in southern Brazil

2018 ◽  
Vol 36 (2) ◽  
pp. 555-564 ◽  
Author(s):  
Everton Frigo ◽  
Francesco Antonelli ◽  
Djeniffer S. S. da Silva ◽  
Pedro C. M. Lima ◽  
Igor I. G. Pacca ◽  
...  
Keyword(s):  
Solar Activity ◽  
Cosmic Rays ◽  
Cosmic Ray ◽  
Galactic Cosmic Rays ◽  
Southern Brazil ◽  
Solar Cycles ◽  
Annual Average ◽  
Average Temperature ◽  
Weather Stations ◽  
Annual Average Temperature

Abstract. Quasi-periodic variations in solar activity and galactic cosmic rays (GCRs) on decadal and bidecadal timescales have been suggested as a climate forcing mechanism for many regions on Earth. One of these regions is southern Brazil, where the lowest values during the last century were observed for the total geomagnetic field intensity at the Earth's surface. These low values are due to the passage of the center of the South Atlantic Magnetic Anomaly (SAMA), which crosses the Brazilian territory from east to west following a latitude of ∼ 26∘. In areas with low geomagnetic intensity, such as the SAMA, the incidence of GCRs is increased. Consequently, possible climatic effects related to the GCRs tend to be maximized in this region. In this work, we investigate the relationship between the ∼ 11-year and ∼ 22-year cycles that are related to solar activity and GCRs and the annual average temperature recorded between 1936 and 2014 at two weather stations, both located near a latitude of 26∘ S but at different longitudes. The first of these stations (Torres – TOR) is located in the coastal region, and the other (Iraí – IRA) is located in the interior, around 450 km from the Atlantic Ocean. Sunspot data and the solar modulation potential for cosmic rays were used as proxies for the solar activity and the GCRs, respectively. Our investigation of the influence of decadal and bidecadal cycles in temperature data was carried out using the wavelet transform coherence (WTC) spectrum. The results indicate that periodicities of 11 years may have continuously modulated the climate at TOR via a nonlinear mechanism, while at IRA, the effects of this 11-year modulation period were intermittent. Four temperature maxima, separated by around 20 years, were detected in the same years at both weather stations. These temperature maxima are almost coincident with the maxima of the odd solar cycles. Furthermore, these maxima occur after transitions from even to odd solar cycles, that is, after some years of intense GCR flux. The obtained results offer indirect mathematical evidence that solar activity and GCR variations contributed to climatic changes in southern Brazil during the last century. A comparison of the results obtained for the two weather stations indicates that the SAMA also contributes indirectly to these temperature variations. The contribution of other mechanisms also related to solar activity cannot be excluded. Keywords. Meteorology and atmospheric dynamics (climatology)

Feasibility Assessment for ORC Generation System Development Using Low Temperature Geothermal Water

2014 ◽  
Author(s):  
Seonghee Kho ◽  
Jayoung Ki ◽  
Myoungcheol Kang
Keyword(s):  
Hot Springs ◽  
System Development ◽  
Exceptional Case ◽  
Economic Feasibility ◽  
Geothermal Water ◽  
Operational Environment ◽  
Generation System ◽  
Annual Average ◽  
Average Temperature ◽  
Annual Average Temperature

Since around 70°C of geothermal water exists in Seokmo-do of Republic of Korea, this study is to assess the feasibility of electricity generation by utilizing ORC system, and the pertinent economic impact. It is generally believed that economic feasibility can be secured only when the source of geothermal water is above 100°C in order to generate electricity by operating ORC system. However, there was an exceptional case that ORC system was commercialized by Pratt-Whitney for around 70 °C of geothermal water in the hot springs of Chena, Alaska. The annual average temperature in the hot springs of Chena, Alaska is approximately 1°C whereas that of Seokmo-do is around 11°C, which makes 10°C of annual average temperature difference in operational environment between the two. Thus, the 2 phases of absorption refrigerating machine is considered for the ORC generation system. With establishing ORC system in consideration of operational environment, the feasibility of the development of ORC system in Seokmo-do is assessed by performance analysis and economic feasibility. As a result of the assessment, it is identified that the economic feasibility can be secured if the price of electricity is over $0.42/kWh same as that of photovoltaic generation as an incentive of the RPS program granted by the Korean government.

scholarly journals INFLUENCE OF TEMPERATURE AND ALTITUDE ON THE EXPANSION OF COFFEE CROPS IN MATAS DE MINAS, BRAZIL

2020 ◽  
Vol 28 ◽  
pp. 157-165
Author(s):  
Karine Rabelo Oliveira ◽  
Williams Pinto Marques Ferreira ◽  
Humberto Paiva Fonseca ◽  
Cecília Fátima Souza
Keyword(s):  
Area Under The Curve ◽  
Growth Potential ◽  
Maximum Temperature ◽  
Annual Average ◽  
Jackknife Test ◽  
Average Temperature ◽  
Annual Minimum Temperature ◽  
Precipitation Seasonality ◽  
Omission Rate ◽  
Annual Average Temperature

Coffee is among the most significant products in Brazil. Minas Gerais is the largest state producer of Arabica coffee. Coffee activity has excellent growth potential, which justifies the identification of new areas for expansion of the culture. This study aimed to determine factors that affect the spatial distribution of coffee plantations the most, as well as to identify areas with a greater aptitude for its expansion in the region of the Matas de Minas (63 municipalities). The MaxEnt software was used to elaborate a model capable of describing the area with the highest potential for estimating the probability of coffee adequacy. The elaboration of the model considered the records of occurrence, climatic and topographic variables of Matas de Minas, the second largest state producing region. The area under the curve (AUC), the omission rate and the Jackknife test were used for validation and analysis of the model. The model was accurate with an AUC of 0.816 and omission rate of 0.54% for the ‘test’. It was identified that the potential distribution of coffee in Matas de Minas is determined by changes in the annual maximum temperature, although it did not generate a significant gain when omitted, accounting for a considerable loss in the model. However, the most influential variables on the delineation of distribution were, the altitude and the annual average temperature. The most favorable areas for expansion of coffee culture in the Matas de Minas were found in the vicinity of the region of Alto Caparaó.Abbreviations used: A1 (altitude); A2 (maximum annual temperature); A3 (annual minimum temperature); BIO 1 (annual average temperature 1); BIO 4 (temperature seasonality), BIO 12 (annual precipitation); BIO 15 (precipitation seasonality); csv (comma-separated values); AUC (area under the curve).

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