Spatial pattern recognition for near-surface high temperature increases in mountain areas using MODIS and SRTM DEM

Abrupt near-surface temperature changes in mountainous areas are a special component of the mountain climate system.Fast and accurate measurements of the locations,intensity,and width of the near-surface changes are necessary but highly difficult due to the complicated environmental conditions and instrumental issues.This paper develops a spatial pattern recognition method to measure the near-surface high temperature increase(NSHTI),one of the lesser-attended changes.First,raster window measurement was proposed to calculate the temperature lapse rate using MODIS land surface temperature and SRTM DEM data.It fully considers the terrain heights of two neighboring cells on opposite or adjacent slopes with a moving window of 3×3 cell size.Second,a threshold selection was performed to identify the NSHTI cells using a threshold of-0.65℃/100 m.Then,the NSHTI strips were parameterized through raster vectorization and spatial analysis.Taking Yunnan,a mountainous province in southwestern China,as the study area,the results indicate that the NSHTI cells concentrate in a strip-like pattern along the mountains and valleys,and the strips are almost parallel to the altitude contours with a slight northward uplift.Also,they are located mostly at a 3/5 height of high mountains or within 400 m from the valley floors,where the controlling topographic index is the altitude of the terrain trend surface but not the absolute elevation and the topographic uplift height and cutting depth.Additionally,the NSHTI intensity varies with the geographic locations and the proportions increase with an exponential trend,and the horizontal width has a mean of about 1000 m and a maximum of over 5000 m.The result demonstrates that the proposed method can effectively recognize NSHTI boundaries over mountains,providing support for the modeling of weather and climate systems and the development of mountain resources.

Review on the Impact of Climate Change on Great Lakes Region’s Agriculture and Water Resources

This study investigates the multifaceted impacts of climate change on the Midwest region of the United States, particularly the rising temperatures and precipitation brought about by hot weather activities and technological advances since the 19th century. From 1900 to 2010, temperatures in the Midwest rose by an average of 1.5 degrees Fahrenheit, which would also lead to an increase in greenhouse gas emissions. Precipitation is also expected to increase due to increased storm activity and changes in regional weather patterns. This paper explores the impact of these changes on urban and agricultural areas. In urban areas such as the city of Chicago, runoff from the increasing impervious surface areas poses challenges to the drainage system, and agriculture areas are challenged by soil erosion, nutrient loss, and fewer planting days due to excessive rainfall. Sustainable solutions such as no-till agriculture and the creation of grassland zones are discussed. Using historical data, recent climate studies and projections, the paper Outlines ways to enhance the Midwest’s ecology and resilience to climate change.

The effect of sea surface temperature increase on the potential habitat of Ommastrephes bartramii in the Northwest Pacific Ocean

In the Northwest Pacific Ocean, the squid jigging fisheries from China, Japan and other countries and regions have targeted the west winter-spring cohort of neon flying squid（Ommastrephes bartramii） from August to November since the 1970 s. This squid is a short-lived ecological opportunist with a life-span of about one year,and its population is labile and recruitment variability is driven by the environment or climate change. This variability provides a challenge for ones to forecast the key habitats affected by climate change. The catch data of O. bartramii from Chinese squid jigging fishery and the satellite-derived sea surface temperature（SST） data are used in the Northwest Pacific Ocean from August to November of 1998 to 2004, the SST preferences of O.bartramii corresponding to high values of catch per fishing day（CPUE） are determined and monthly potential habitats are predicted using a histogram analysis of the SST data. The possible changes in the potential habitats of O. bartramii in the Northwest Pacific Ocean are estimated under four climate change scenarios based on the Fourth Assessment Report（AR4） of the Intergovernmental Panel on Climate Change, i.e., 0.5, 1, 2 and 4°C increases in the SST because of the climate change. The results reveal an obvious poleward shift of the potential habitats of O. bartramii in the Northwest Pacific Ocean.

ESTIMATION OF THE CRITICAL RATE OF TEMPERATURE INCREASE OF THERMAL EXPLOSION OF NITROCELLULOSE USING NON-ISOTHERMAL DSC

A method of estimating the critical rate of temperature increase of thermal explosion for the first orderautocatalytic decomposition reaction system using non-isothermal DSC is presented. Information is obtained on theincreasing rate of temperature in nitrocellulose containing 13.54% of nitrogen when the first order autocatalytic decomposition converts into thermal explosion.

Fatty acids in microalgae and cyanobacteria in a changing world:Contrasting temperate and cold environments

Under the present changing climate conditions and the observed temperature increase,it is of high importance to understand its effects on aquatic microbial life,and organisms’adaptations at the biochemical level.To adjust to temperature or salinity stress and avoid cell damage,organisms alter their degree of fatty acids(FAs)saturation.Thus,temperature is expected to have strong effects on both the quantity and quality of FAs in aquatic microorganisms.Here we review some recent findings about FAs sensitivity to climate change in contrasting environments.Overall,heat waves may induce changes in the relative abundance of polyunsaturated FAs(PUFA).However,the impact of the exposure to warming waters is different in temperate and polar environments.In cold marine waters,high concentration of omega-3(ω3)FAs such as eicosapentaenoic acid(EPA)is promoted due to the activation of the desaturase enzyme.In this way,cells have enough energy to produce or activate antioxidant protection mechanisms and avoid oxidative stress due to heat waves.Contrastingly,under high irradiance and heat wave conditions in temperate environments,photosystems’protection is achieved by decreasing EPA concentration due to desaturase sensitivity.Essential FAs are transferred in aquatic food webs.Therefore,any alteration in the production of essential FAs by phytoplankton(the main source ofω3)due to climate warming can be transferred to higher trophic levels,with cascading effects for the entire aquatic ecosystem.

Key global climate governance problems and Chinese countermeasures

Presently,the full implementation of the negotiations and collaborations under the Paris Agreement faces new key problems and severe challenges.These problems and challenges include the following:how to honor the principle of“common but differentiated responsibilities”to facilitate a comprehensive,balanced,and effective implementation of the key elements of the Paris Agreement,such as adaptation,mitigation,finance,technology,capacity building,and transparency;how to uphold and maintain the status of China and other emerging countries as developing countries in light of the requirements of the United Nations Framework Convention on Climate Change and the historical responsibilities of these countries;and how to assess the goal of limiting the global temperature increase to 1.5℃and what constitutes an equitable carbon mitigation pathway for different types of countries.Developed countries and developing countries have drastically diverging views on carbon border adjustment measures for trade with developing countries proposed by several developed countries such as the European Union.Developed countries have demonstrated obvious intentions and actions designed to weaken and neglect the principle of“common but differentiated responsibilities”,to impose mitigation pressure on developing countries,to shift the responsibilities for emissions onto others,and to pass on the costs of mitigation.The maneuvering among different types of countries and interest groups has become increasingly intense.In response,China must maintain its strategic focus,adhere to the goals and principles established by the Paris Agreement,stick to its strategic positioning as a developing country,solidify strategic support from the developing world,and safeguard the legitimate rights and interests of developing countries.China played a conducive role in facilitating the Paris Agreement and has become an active participant,contributor,and leader in global climate governance.China must continue to follow Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era and its conception of ecological civilization and the concept of building a community of common destiny,to actively lead the cooperation process in the construction of a global climate governance system characterized by equity,justice,and win-win collaborations,and to promote compliance with the Paris Agreement.At the same time,China should accelerate the green,low-carbon,circular transformation of its economy;accelerate the coordinated governance of the economy,environment,and climate change;and formulate and implement a long-term low-carbon development strategy.By the middle of the 21st century,while achieving the goal of building a great modern socialist country,China can also achieve a deep decarbonization development path that is in line with the goal of limiting the global temperature increase to well below 2°C and pursuing efforts to limit the increase to 1.5℃.

Monitoring Day and Night-Time Situation of Urban Heat Island and Possible Adaptation Measures in Douala, Cameroon

Urban Heat Island (UHI) has the potential to directly influence the health and welfare of urban residents. The study employed a traditional method called “paired measurement program” to analyze the effects of four land use/land- cover patterns on intra-urban air temperature variations in the Douala Metropolis, Cameroon under different atmospheric conditions. This study also investigated the possible adaptation measures employed by the inhabitants to combat the urban heat island effects. The result revealed a variation in the temperature of the selected transects. There was a mix of cool and heat islands by day, especially during rainy seasons. The daytime variations were strongly correlated to the amount of tree shading. It was also observed that the temperature gradient was formed at the Central Business District (CBD) and progressively lowered to the suburbs. The thermal comfort classification for the area ranges between 25.4°C and 27°C, which is a class where over 50% of the population feels stressed;and the range of 32°C and above, where most of the population suffers discomfort. In order to investigate the possible adaptation measures employed by the inhabitants of Douala, two hundred and fifty questionnaires were distributed and analyzed using descriptive statistics. The result revealed that the inhabitants use various coping strategies in order to adapt to UHI effects. The strategies identified include;stay indoors, drink plenty of water, wear light clothing, go to an A/C location, take a cool shower, avoid outdoors, and wear a hat or cover head. The widely used coping strategy identified is drinking plenty of water. The expensive nature of A/C makes it the least used coping strategy.

Effect of elevated CO_(2) concentration on growth course of tree seedlings in Changbai Mountain

One-year-old seedlings of Pinus koraiensis, Pinus sylvestriformis, Phellodendron amurense were grown in open-top chambers (OTCs) with 700 and 500 (mol/mol CO2 concentrations, control chamber and on open site (ambient CO2, about 350 (mol/mol CO2) respectively at the Open Research Station of Changbai Mountain Forest Ecosystems, Chinese Academy of Sciences, and the growth course responses of three species to elevated CO2 and temperature during one growing season was studied from May to Oct. 1999. The results showed that increase in CO2 concentration enhanced the growth of seedlings and the effect of 700 (mol/mol CO2 was more remarkable than 500 (mol/mol CO2 on seedling growth. Under the condition of doubly elevated CO2 concentration, the biomass increased by 38% in average for coniferous seedlings and 60% for broad-leaved seedlings. With continuous treatment of high CO2 concentration, the monthly-accumulated biomass of shade-tolerant Pinus koraiensis seedlings was bigger in July than in August and September, while those of Pinus sylvestriformis and Phellodendron amurense seedlings showed an increase in July and August, or did not decrese until September. During the hot August, high CO2 concentration enhanced the growth of Pinus koraiensis seedlings by increasing temperature, but it did not show dominance in other two species.

Enhancing crop yield by using Rubisco activase to improve photosynthesis under elevated temperatures

With the rapid growth of world population,it is essential to increase agricultural productivity to feed the growing population.Over the past decades,many methods have been used to increase crop yields.Despite the success in boosting the crop yield through these methods,global food production still needs to be increased to be on par with the increasing population and its dynamic consumption patterns.Additionally,given the prevailing environmental conditions pertaining to the global temperature increase,heat stress will likely be a critical factor that negatively affects plant biomass and crop yield.One of the key elements hindering photosynthesis and plant productivity under heat stress is the thermo-sensitivity of the Rubisco activase(RCA),a molecular chaperone that converts Rubisco back to active form after it becomes inactive.It would be an attractive and practical strategy to maintain photosynthetic activity under elevated temperatures by enhancing the thermo-stability of RCA.In this context,this review discusses the need to improve the thermo-tolerance of RCA under current climatic conditions and to further study RCA structure and regulation,and its limitations at elevated temperatures.This review summarizes successful results and provides a perspective on RCA research and its implication in improving crop yield under elevated temperature conditions in the future.

Fluidization behavior of graphitized glassy particles in a fluidized carbon bed cooling process for investment casting

Fluidized Carbon Bed Cooling(FCBC)is an innovative investment casting process for directional solidification of superalloy components.It takes advantage of a fluidized bed with a base of small glassy carbon beads for cooling and other low-density particles that form an insulating layer by floating to the bed surface.This so-called“Dynamic Baffle”protects the fluidized bed from the direct heat input from the high-temperature heating zone and provides the basis for an improved bed microstructure.The prerequisites for a stable casting process are stable fluidization conditions where neither collapse of the bed nor particle blow out at excessive bubble formation occur.This work aimed to investigate the fluidization behavior of spherical carbon bed material in argon and air at temperatures between 20 to 350℃.Systematic studies at reduced pressures using the FCBC prototype device were performed to understand the stable fluidization conditions at all stages of the investment casting process.The particle shape factor and size distribution characterization and the measurement of the powder’s minimum fluidization velocity and bed voidage show that this material can be fully utilized as a cooling and buoyancy medium during the FCBC process.

加拿大北极地区航运对气候变暖的影响

This paper presents a detailed account of the effect of shipping activity on the increasing trends of air temperatures in the Canadian Arctic region for the period of 1980–2018.Increasing trend of temperature has gained significant attention with respect to shipping activities and sea ice area in the Canadian Arctic.Temperature,sea ice area and shipping traffic datasets were investigated,and simple linear regression analyses were conducted to predict the rate of change(per decade)of the average temperature,considering winter(January)and summer(July)seasons.The results indicate that temperature generally increased over the studied region.Significant warming trend was observed during July,with an increase of up to 1℃,for the Canadian Arctic region.Such increasing trend of temperature was observed during July from the lower to higher latitudes.The increase in temperature during July is speculated to increase the melting of ice.Results also show a decline in sea ice area has a significant positive effect on the shipping traffic,and the numbers of marine vessel continue to increase in the region.The increase in temperature causes the breaking of sea ice due to shipping activities over northern Arctic Canada.