Heating in the ocean has continued in 2024 in response to increased greenhouse gas concentrations in the atmosphere,despite the transition from an El Ni?o to neutral conditions. In 2024, both global sea surface temper...Heating in the ocean has continued in 2024 in response to increased greenhouse gas concentrations in the atmosphere,despite the transition from an El Ni?o to neutral conditions. In 2024, both global sea surface temperature(SST) and upper2000 m ocean heat content(OHC) reached unprecedented highs in the historical record. The 0–2000 m OHC in 2024exceeded that of 2023 by 16 ± 8 ZJ(1 Zetta Joules = 1021 Joules, with a 95% confidence interval)(IAP/CAS data), which is confirmed by two other data products: 18 ± 7 ZJ(CIGAR-RT reanalysis data) and 40 ± 31 ZJ(Copernicus Marine data,updated to November 2024). The Indian Ocean, tropical Atlantic, Mediterranean Sea, North Atlantic, North Pacific, and Southern Ocean also experienced record-high OHC values in 2024. The global SST continued its record-high values from2023 into the first half of 2024, and declined slightly in the second half of 2024, resulting in an annual mean of 0.61°C ±0.02°C(IAP/CAS data) above the 1981–2010 baseline, slightly higher than the 2023 annual-mean value(by 0.07°C ±0.02°C for IAP/CAS, 0.05°C ± 0.02°C for NOAA/NCEI, and 0.06°C ± 0.11°C for Copernicus Marine). The record-high values of 2024 SST and OHC continue to indicate unabated trends of global heating.展开更多
The increased concentration of greenhouse gases in the atmosphere from human activities traps heat within the climate system and increases ocean heat content(OHC). Here, we provide the first analysis of recent OHC cha...The increased concentration of greenhouse gases in the atmosphere from human activities traps heat within the climate system and increases ocean heat content(OHC). Here, we provide the first analysis of recent OHC changes through 2021 from two international groups. The world ocean, in 2021, was the hottest ever recorded by humans, and the 2021 annual OHC value is even higher than last year’s record value by 14 ± 11 ZJ(1 zetta J = 1021 J) using the IAP/CAS dataset and by16 ± 10 ZJ using NCEI/NOAA dataset. The long-term ocean warming is larger in the Atlantic and Southern Oceans than in other regions and is mainly attributed, via climate model simulations, to an increase in anthropogenic greenhouse gas concentrations. The year-to-year variation of OHC is primarily tied to the El Nino-Southern Oscillation(ENSO). In the seven maritime domains of the Indian, Tropical Atlantic, North Atlantic, Northwest Pacific, North Pacific, Southern oceans,and the Mediterranean Sea, robust warming is observed but with distinct inter-annual to decadal variability. Four out of seven domains showed record-high heat content in 2021. The anomalous global and regional ocean warming established in this study should be incorporated into climate risk assessments, adaptation, and mitigation.展开更多
Changes in ocean heat content(OHC), salinity, and stratification provide critical indicators for changes in Earth’s energy and water cycles. These cycles have been profoundly altered due to the emission of greenhouse...Changes in ocean heat content(OHC), salinity, and stratification provide critical indicators for changes in Earth’s energy and water cycles. These cycles have been profoundly altered due to the emission of greenhouse gasses and other anthropogenic substances by human activities, driving pervasive changes in Earth’s climate system. In 2022, the world’s oceans, as given by OHC, were again the hottest in the historical record and exceeded the previous 2021 record maximum.According to IAP/CAS data, the 0–2000 m OHC in 2022 exceeded that of 2021 by 10.9 ± 8.3 ZJ(1 Zetta Joules = 1021Joules);and according to NCEI/NOAA data, by 9.1 ± 8.7 ZJ. Among seven regions, four basins(the North Pacific, North Atlantic, the Mediterranean Sea, and southern oceans) recorded their highest OHC since the 1950s. The salinity-contrast index, a quantification of the “salty gets saltier–fresh gets fresher” pattern, also reached its highest level on record in 2022,implying continued amplification of the global hydrological cycle. Regional OHC and salinity changes in 2022 were dominated by a strong La Ni?a event. Global upper-ocean stratification continued its increasing trend and was among the top seven in 2022.展开更多
Human-emitted greenhouse gases(GHGs)have resulted in a long-term and unequivocal warming of the planet(IPCC,2019).More than 90%of the excess heat is stored within the world's oceans,where it accumulates and causes...Human-emitted greenhouse gases(GHGs)have resulted in a long-term and unequivocal warming of the planet(IPCC,2019).More than 90%of the excess heat is stored within the world's oceans,where it accumulates and causes increases in ocean temperature(Rhein et al.,2013;Abram et al.,2019).展开更多
The long-term warming of the ocean is a critical indicator of both the past and present state of the climate system. It also provides insights about the changes to come, owing to the persistence of both decadal variat...The long-term warming of the ocean is a critical indicator of both the past and present state of the climate system. It also provides insights about the changes to come, owing to the persistence of both decadal variations and secular trends,which the ocean records extremely well(Hansen et al., 2011;IPCC, 2013;Rhein et al., 2013;Trenberth et al., 2016;Abram et al., 2019).展开更多
Ocean heat content(OHC)change contributes substantially to global sea level rise,so it is a vital task for the climate research community to estimate historical OHC.While there are large uncertainties regarding its va...Ocean heat content(OHC)change contributes substantially to global sea level rise,so it is a vital task for the climate research community to estimate historical OHC.While there are large uncertainties regarding its value,in this study,the authors discuss recent progress to reduce the errors in OHC estimates,including corrections to the systematic biases in expendable bathythermograph(XBT)data,filling gaps in the data,and choosing a proper climatology.These improvements lead to a better reconstruction of historical upper(0–700 m)OHC change,which is presented in this study as the Institute of Atmospheric Physics(IAP)version of historical upper OHC assessment.Challenges still remain;for example,there is still no general consensus on mapping methods.Furthermore,we show that Coupled Model Intercomparison Project,Phase 5(CMIP5)simulations have limited ability in capturing the interannual and decadal variability of historical upper OHC changes during the past 45 years.展开更多
The global physical and biogeochemical environment has been substantially altered in response to increased atmospheric greenhouse gases from human activities.In 2023,the sea surface temperature(SST)and upper 2000 m oc...The global physical and biogeochemical environment has been substantially altered in response to increased atmospheric greenhouse gases from human activities.In 2023,the sea surface temperature(SST)and upper 2000 m ocean heat content(OHC)reached record highs.The 0–2000 m OHC in 2023 exceeded that of 2022 by 15±10 ZJ(1 Zetta Joules=1021 Joules)(updated IAP/CAS data);9±5 ZJ(NCEI/NOAA data).The Tropical Atlantic Ocean,the Mediterranean Sea,and southern oceans recorded their highest OHC observed since the 1950s.Associated with the onset of a strong El Niño,the global SST reached its record high in 2023 with an annual mean of~0.23℃ higher than 2022 and an astounding>0.3℃ above 2022 values for the second half of 2023.The density stratification and spatial temperature inhomogeneity indexes reached their highest values in 2023.展开更多
The increasing heat-trapping gases emitted by human activities into the atmosphere produce an energy imbalance between incoming solar radiation and outgoing longwave radiation that leads to global heating(Rhein et al....The increasing heat-trapping gases emitted by human activities into the atmosphere produce an energy imbalance between incoming solar radiation and outgoing longwave radiation that leads to global heating(Rhein et al.,2013;Trenberth et al.,2014;von Schuckmann et al.,2016).The vast majority of global warming heat ends up deposited in the world’s oceans,and ocean heat content(OHC)change is one of the best—if not the best—metric for climate change(Cheng et al.,2019).In 2018,continued record heat was measured in the Earth’s climate system.In fact,2018 has set a new record of ocean heating,surpassing 2017,which was the previous warmest year ever recorded(Cheng et al.,2018)(Fig.1).展开更多
This paper includes a comprehensive assessment of 40 models from the Coupled Model Intercomparison Project phase 5(CMIP5)and 33 models from the CMIP phase 6(CMIP6)to determine the climatological and seasonal variation...This paper includes a comprehensive assessment of 40 models from the Coupled Model Intercomparison Project phase 5(CMIP5)and 33 models from the CMIP phase 6(CMIP6)to determine the climatological and seasonal variation of ocean salinity from the surface to 2000 m.The general pattern of the ocean salinity climatology can be simulated by both the CMIP5 and CMIP6 models from the surface to 2000-m depth.However,this study shows an increased fresh bias in the surface and subsurface salinity in the CMIP6 multimodel mean,with a global average of−0.44 g kg^(−1) for the sea surface salinity(SSS)and−0.26 g kg^(−1) for the 0-1000-m averaged salinity(S1000)compared with the CMIP5 multimodel mean(−0.25 g kg^(−1) for the SSS and−0.07 g kg^(−1) for the S1000).In terms of the seasonal variation,both CMIP6 and CMIP5 models show positive(negative)anomalies in the first(second)half of the year in the global average SSS and S1000.The model-simulated variation in SSS is consistent with the observations,but not for S1000,suggesting a substantial uncertainty in simulating and understanding the seasonal variation in subsurface salinity.The CMIP5 and CMIP6 models overestimate the magnitude of the seasonal variation of the SSS in the tropics in the region 20°S-20°N but underestimate the magnitude of the seasonal change in S1000 in the Atlantic and Indian oceans.These assessments show new features of the model errors in simulating ocean salinity and support further studies of the global hydrological cycle.展开更多
The Sumampa River in Mampong-Ashanti in Ghana is a very important river that supplies water to the water processing company for treatment for the whole community and its environs. In spite of its importance, the buffe...The Sumampa River in Mampong-Ashanti in Ghana is a very important river that supplies water to the water processing company for treatment for the whole community and its environs. In spite of its importance, the buffer area of the river has been encroached by settlers. Residential houses sited along the river have channeled their waste water into the river and several anthropogenic activities go on along the river. Therefore, this study was conducted to assess the effects of anthropogenic activities on the quality of the river. Water samples were collected from various parts of the river including the source and outflow for physico-chemical and microbial analyses. The results showed that, the water was highly turbid with high total dissolved solids at some points because of intense anthropogenic activities. High turbidity and total dissolved solids greatly influence the microbial load of the water. We therefore recommend that measures are put in place to protect the Sumampa River through the creation of a buffer zone by planting trees along the banks of the river. The trees could help detoxify the run-off water that flows into the river.展开更多
‘Selfie’taking was introduced to the common people by smartphones and has become a common practice across the globe in no time.With technological advancement and the popularity of smartphones,selfie-taking has grown...‘Selfie’taking was introduced to the common people by smartphones and has become a common practice across the globe in no time.With technological advancement and the popularity of smartphones,selfie-taking has grown rapidly within a short time.In light of the new trend set by the generation,this study aimed to explore reasons for selfie-taking and selfie-posting on social media and their effects on the social and psychological lives of young adults.A purposive sampling method was adopted to select 20 Indian citizens,between 18 and 24 years.The data were collected through semi-structured interviews and analysed using thematic analysis.Selfie-taking and posting on social media give positive feelings,and it acts as a mood modifier dependent mostly on the favourability and feedback about the post which in turn affects emotions and self-satisfaction.展开更多
Dealing with kinetic energy is one of the most important problems in hydraulic structures,and this energy can damage downstream structures.This study aims to study energy dissipation of supercritical water flow passin...Dealing with kinetic energy is one of the most important problems in hydraulic structures,and this energy can damage downstream structures.This study aims to study energy dissipation of supercritical water flow passing through a sudden contraction.The experiments were conducted on a sudden contraction with 15 cm width.A 30 cm wide flume was installed.The relative contraction ranged from 8.9 to 9.7,where relative contraction refers to the ratio of contraction width to initial flow depth.The Froude value in the investigation varied from 2 to 7.The contraction width of numerical simulation was 5~15 cm,the relative contraction was 8.9~12.42,and the Froude value ranged from 8.9~12.42.In order to simulate turbulence,the k-εRNG model was harnessed.The experimental and numerical results demonstrate that the energy dissipation increases with the increase of Froude value.Also,with the sudden contraction,the rate of relative depreciation of energy is increased due to the increase in backwater profile and downstream flow depth.The experimentation verifies the numerical results with a correlation coefficient of 0.99 and the root mean square error is 0.02.展开更多
The potential effect of canopy cover on the quality of River Offin which serves as drinking water for communities including Hwediem, Mprim and Boanim in the Mampong Municipality of the Ashanti region of Ghana was stud...The potential effect of canopy cover on the quality of River Offin which serves as drinking water for communities including Hwediem, Mprim and Boanim in the Mampong Municipality of the Ashanti region of Ghana was studied. These communities exemplify Ghanaian farming communities. Often, rural farmers do not have access to clean water. Using the part of the river serving these communities as a test case, we assessed the quality of water along a gradient of three different levels of canopy cover (closed, semi-closed and open canopy) where residents frequently access water. Physico-chemical tests showed that, the level of most of the physical and chemical properties of the water under all three different canopy covers was within the acceptable limits set by the World Health Organization. There was low turbidity where the canopy was closed resulting in relatively lower faecal coliforms. Total dissolved solids were also less where canopy cover was closed. Therefore, the general water quality could be potentially improved by planting trees along the river to form canopy.展开更多
Long-term, body-adhered medical devices rely on an adhesive interface to maintain contact with the patient. The greatest threat to on-body adhesion is mechanical stress imparted on the medical device. Several factors ...Long-term, body-adhered medical devices rely on an adhesive interface to maintain contact with the patient. The greatest threat to on-body adhesion is mechanical stress imparted on the medical device. Several factors contribute to the ability of the device to withstand such stresses, such as the mechanical design, shape, and size of the device. This analysis investigates the impact that design changes to the device have on the stress and strain experienced by the system when acted on by a stressor. The analysis also identifies the design changes that are most effective at reducing the stress and strain. An explicit dynamic finite element analysis method was used to simulate several design iterations and a regression analysis was performed to quantify the relationship between design and resultant stress and strain. The shape, height, size, and taper of the medical device were modified, and the results indicate that, to reduce stress and strain in the system, the device should resemble a square in shape, be short in height, and small in size with a large taper. The square shape experienced 17.5% less stress compared to the next best performing shape. A 10% reduction in device height resulted in a 21% reduction in stress and 24% reduction in strain. A 20% reduction in device size caused a 7% reduction in stress and 2% reduction in strain. A 20% increase in device taper size led to a negligible reduction in stress and a 6% reduction in strain. The height of the device had the greatest impact on the resultant stress and strain.展开更多
The introduction of invasive insect pests across national borders has become a major concern in crop production. Accordingly, national plant protection organizations are challenge to reinforce their monitoring strateg...The introduction of invasive insect pests across national borders has become a major concern in crop production. Accordingly, national plant protection organizations are challenge to reinforce their monitoring strategies, which are hampered by the weight and size of inspection equipment, as well as the taxonomic extensiveness of interrupted species. Moreover, some insect pests that impede farmer productivity and profitability are difficult for researchers to address on time due to a lack of appropriate plant protection measures. Farmers’ reliance on synthetic pesticides and biocontrol agents has resulted in major economic and environmental ramifications. DNA barcoding is a novel technology that has the potential to improve Integrated Pest Management decision-making, which is dependent on the ability to correctly identify pest and beneficial organisms. This is due to some natural traits such as phenology or pesticide susceptibility browbeaten by IPM strategies to avert pest establishment. Specifically, Deoxyribonucleic acid (DNA) sequence information was applied effectively for the identification of some micro-organisms. This technology, DNA barcoding, allows for the identification of insect species by using short, standardized gene sequences. DNA barcoding is basically based on repeatable and accessible technique that allows for the mechanisation or automation of species discrimination. This technique bridges the taxonomic bio-security gap and meets the International Plant Protection Convention diagnostic standards for insect identification. This review therefore discusses DNA barcoding as a technique for insect pests’ identification and its potential application for crop protection.展开更多
基金supported by the National Key R&D Program of China (Grant No.2023YFF0806500)the International Partnership Program of the Chinese Academy of Sciences (Grant No.060GJHZ2024064MI)+10 种基金the Chinese Academy of Sciences and the National Research Council of Italy Scientific Cooperative Programmethe new Cornerstone Science Foundation through the XPLORER PRIZEthe National Key Scientific and Technological Infrastructure project “Earth System Science Numerical Simulator Facility” (Earth Lab), and Ocean Negative Carbon Emissions (ONCE)sponsored by the US National Science Foundationsupported by the Young Talent Support Project of Guangzhou Association for Science and Technologythe Open Research Cruise NORC2022-10+NORC2022-303 supported by NSFC shiptime Sharing Projects 42149910supported by NASA Awards 80NSSC17K0565, 80NSSC21K1191, and 80NSSC22K0046by the Regional and Global Model Analysis (RGMA) component of the Earth and Environmental System Modeling Program of the U.S.Department of Energy’s Office of Biological & Environmental Research (BER) via National Science Foundation IA 1947282supported by NOAA (Grant No.NA19NES4320002 to CISESS-MD at the University of Maryland)supported by the Austrian Science Fund (P33177)ESA (contract ref.4000145298/24/I-LR)。
文摘Heating in the ocean has continued in 2024 in response to increased greenhouse gas concentrations in the atmosphere,despite the transition from an El Ni?o to neutral conditions. In 2024, both global sea surface temperature(SST) and upper2000 m ocean heat content(OHC) reached unprecedented highs in the historical record. The 0–2000 m OHC in 2024exceeded that of 2023 by 16 ± 8 ZJ(1 Zetta Joules = 1021 Joules, with a 95% confidence interval)(IAP/CAS data), which is confirmed by two other data products: 18 ± 7 ZJ(CIGAR-RT reanalysis data) and 40 ± 31 ZJ(Copernicus Marine data,updated to November 2024). The Indian Ocean, tropical Atlantic, Mediterranean Sea, North Atlantic, North Pacific, and Southern Ocean also experienced record-high OHC values in 2024. The global SST continued its record-high values from2023 into the first half of 2024, and declined slightly in the second half of 2024, resulting in an annual mean of 0.61°C ±0.02°C(IAP/CAS data) above the 1981–2010 baseline, slightly higher than the 2023 annual-mean value(by 0.07°C ±0.02°C for IAP/CAS, 0.05°C ± 0.02°C for NOAA/NCEI, and 0.06°C ± 0.11°C for Copernicus Marine). The record-high values of 2024 SST and OHC continue to indicate unabated trends of global heating.
基金supported by the National Natural Science Foundation of China(Grant No.42122046,42076202)Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB42040402)+5 种基金National Natural Science Foundation of China(Grant No.42076202)National Key R&D Program of China(Grant No.2017YFA0603202)Key Deployment Project of Centre for Ocean Mega-Research of Science,CAS(Grant Nos.COMS2019Q01 and COMS2019Q07)NCAR is sponsored by the US National Science Foundationsupported by NASA Award 80NSSC17K0565the Regional and Global Model Analysis(RGMA)component of the Earth and Environmental System Modeling Program of the U.S.Department of Energy’s Office of Biological&Environmental Research(BER)via National Science Foundation IA 1844590。
文摘The increased concentration of greenhouse gases in the atmosphere from human activities traps heat within the climate system and increases ocean heat content(OHC). Here, we provide the first analysis of recent OHC changes through 2021 from two international groups. The world ocean, in 2021, was the hottest ever recorded by humans, and the 2021 annual OHC value is even higher than last year’s record value by 14 ± 11 ZJ(1 zetta J = 1021 J) using the IAP/CAS dataset and by16 ± 10 ZJ using NCEI/NOAA dataset. The long-term ocean warming is larger in the Atlantic and Southern Oceans than in other regions and is mainly attributed, via climate model simulations, to an increase in anthropogenic greenhouse gas concentrations. The year-to-year variation of OHC is primarily tied to the El Nino-Southern Oscillation(ENSO). In the seven maritime domains of the Indian, Tropical Atlantic, North Atlantic, Northwest Pacific, North Pacific, Southern oceans,and the Mediterranean Sea, robust warming is observed but with distinct inter-annual to decadal variability. Four out of seven domains showed record-high heat content in 2021. The anomalous global and regional ocean warming established in this study should be incorporated into climate risk assessments, adaptation, and mitigation.
基金supported by the National Natural Science Foundation of China (Grant Nos. 42122046 and 42076202)the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB42040402)+4 种基金sponsored by the US National Science Foundationsupported by NASA Awards 80NSSC17K0565 and 80NSSC22K0046by the Regional and Global Model Analysis (RGMA) component of the Earth and Environmental System Modeling Program of the U.S. Department of Energy’s Office of Biological & Environmental Research (BER) via National Science Foundation IA 1947282supported by NOAA (Grant No. NA19NES4320002 to CISESS-MD at the University of Maryland)supported by the Young Talent Support Project of Guangzhou Association for Science and Technology。
文摘Changes in ocean heat content(OHC), salinity, and stratification provide critical indicators for changes in Earth’s energy and water cycles. These cycles have been profoundly altered due to the emission of greenhouse gasses and other anthropogenic substances by human activities, driving pervasive changes in Earth’s climate system. In 2022, the world’s oceans, as given by OHC, were again the hottest in the historical record and exceeded the previous 2021 record maximum.According to IAP/CAS data, the 0–2000 m OHC in 2022 exceeded that of 2021 by 10.9 ± 8.3 ZJ(1 Zetta Joules = 1021Joules);and according to NCEI/NOAA data, by 9.1 ± 8.7 ZJ. Among seven regions, four basins(the North Pacific, North Atlantic, the Mediterranean Sea, and southern oceans) recorded their highest OHC since the 1950s. The salinity-contrast index, a quantification of the “salty gets saltier–fresh gets fresher” pattern, also reached its highest level on record in 2022,implying continued amplification of the global hydrological cycle. Regional OHC and salinity changes in 2022 were dominated by a strong La Ni?a event. Global upper-ocean stratification continued its increasing trend and was among the top seven in 2022.
基金supported by the National Key Research and Development Program of China (Grant Nos. 2016YFC1401806 and 2017YFA0603202)sponsored by the US National Science Foundation+2 种基金funded in partnership with the NOAA OAR Ocean Observing and Monitoring Divisionpartially supported by the Regional and Global Model Analysis (RGMA) component of the Earth and Environmental System Modeling Program of the U.S. Department of Energy’s Office of Biological & Environmental Research (BER) via National Science Foundation IA 1844590supported in part by NSF Award #AGS-1419571
文摘Human-emitted greenhouse gases(GHGs)have resulted in a long-term and unequivocal warming of the planet(IPCC,2019).More than 90%of the excess heat is stored within the world's oceans,where it accumulates and causes increases in ocean temperature(Rhein et al.,2013;Abram et al.,2019).
基金supported by the National Key R&D Program of China (Grant No. 2017YFA0603202)the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB42040402)+4 种基金Key Deployment Project of Centre for Ocean Mega-Research of Science, CAS (Grant No. COMS2019Q01)sponsored by the US National Science Foundationsupported by NASA Award 80NSSC17K0565the Regional and Global Model Analysis (RGMA) component of the Earth and Environmental System Modeling Program of the U.S. Department of Energy's Office of Biological & Environmental Research (BER) via National Science Foundation IA 1844590partially supported by NOAA (grant NA14NES4320003 to CISESS-MD at the University of Maryland)。
文摘The long-term warming of the ocean is a critical indicator of both the past and present state of the climate system. It also provides insights about the changes to come, owing to the persistence of both decadal variations and secular trends,which the ocean records extremely well(Hansen et al., 2011;IPCC, 2013;Rhein et al., 2013;Trenberth et al., 2016;Abram et al., 2019).
基金supported by the Chinese Academy of Sciences project entitled"Western Pacific Ocean System:Structure,Dynamics and Consequences"(Grant No.XDA11010405)the National Natural Science Foundation of China(Grant No.41476016)
文摘Ocean heat content(OHC)change contributes substantially to global sea level rise,so it is a vital task for the climate research community to estimate historical OHC.While there are large uncertainties regarding its value,in this study,the authors discuss recent progress to reduce the errors in OHC estimates,including corrections to the systematic biases in expendable bathythermograph(XBT)data,filling gaps in the data,and choosing a proper climatology.These improvements lead to a better reconstruction of historical upper(0–700 m)OHC change,which is presented in this study as the Institute of Atmospheric Physics(IAP)version of historical upper OHC assessment.Challenges still remain;for example,there is still no general consensus on mapping methods.Furthermore,we show that Coupled Model Intercomparison Project,Phase 5(CMIP5)simulations have limited ability in capturing the interannual and decadal variability of historical upper OHC changes during the past 45 years.
基金supported by the National Natural Science Foundation of China (Grant Nos. 42076202, 42122046, 42206208 and 42261134536)the Open Research Cruise NORC2022-10+NORC2022-303 supported by NSFC shiptime Sharing Projects 42149910+7 种基金the new Cornerstone Science Foundation through the XPLORER PRIZE, DAMO Academy Young Fellow, Youth Innovation Promotion Association, Chinese Academy of SciencesNational Key Scientific and Technological Infrastructure project “Earth System Science Numerical Simulator Facility” (EarthLab)sponsored by the US National Science Foundationsupported by NASA Awards 80NSSC17K0565, 80NSSC21K1191, and 80NSSC22K0046by the Regional and Global Model Analysis (RGMA) component of the Earth and Environmental System Modeling Program of the U.S. Department of Energy’s Office of Biological & Environmental Research (BER) via National Science Foundation IA 1947282supported by NOAA (Grant No. NA19NES4320002 to CISESS-MD at the University of Maryland)supported by the Young Talent Support Project of Guangzhou Association for Science and Technologyfunded by the Istituto Nazionale di Geofisica e Vulcanologia (INGV) in agreement between INGV, ENEA, and GNV SpA shipping company that provides hospitality on its commercial vessels
文摘The global physical and biogeochemical environment has been substantially altered in response to increased atmospheric greenhouse gases from human activities.In 2023,the sea surface temperature(SST)and upper 2000 m ocean heat content(OHC)reached record highs.The 0–2000 m OHC in 2023 exceeded that of 2022 by 15±10 ZJ(1 Zetta Joules=1021 Joules)(updated IAP/CAS data);9±5 ZJ(NCEI/NOAA data).The Tropical Atlantic Ocean,the Mediterranean Sea,and southern oceans recorded their highest OHC observed since the 1950s.Associated with the onset of a strong El Niño,the global SST reached its record high in 2023 with an annual mean of~0.23℃ higher than 2022 and an astounding>0.3℃ above 2022 values for the second half of 2023.The density stratification and spatial temperature inhomogeneity indexes reached their highest values in 2023.
基金supported by the National Key Research and Development Program of China (Grant Nos. 2017YFA0603202 and 2016YFC1401705)
文摘The increasing heat-trapping gases emitted by human activities into the atmosphere produce an energy imbalance between incoming solar radiation and outgoing longwave radiation that leads to global heating(Rhein et al.,2013;Trenberth et al.,2014;von Schuckmann et al.,2016).The vast majority of global warming heat ends up deposited in the world’s oceans,and ocean heat content(OHC)change is one of the best—if not the best—metric for climate change(Cheng et al.,2019).In 2018,continued record heat was measured in the Earth’s climate system.In fact,2018 has set a new record of ocean heating,surpassing 2017,which was the previous warmest year ever recorded(Cheng et al.,2018)(Fig.1).
基金supported by the National Natural Science Foundation of China(Grant No.42076202)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB42040402).
文摘This paper includes a comprehensive assessment of 40 models from the Coupled Model Intercomparison Project phase 5(CMIP5)and 33 models from the CMIP phase 6(CMIP6)to determine the climatological and seasonal variation of ocean salinity from the surface to 2000 m.The general pattern of the ocean salinity climatology can be simulated by both the CMIP5 and CMIP6 models from the surface to 2000-m depth.However,this study shows an increased fresh bias in the surface and subsurface salinity in the CMIP6 multimodel mean,with a global average of−0.44 g kg^(−1) for the sea surface salinity(SSS)and−0.26 g kg^(−1) for the 0-1000-m averaged salinity(S1000)compared with the CMIP5 multimodel mean(−0.25 g kg^(−1) for the SSS and−0.07 g kg^(−1) for the S1000).In terms of the seasonal variation,both CMIP6 and CMIP5 models show positive(negative)anomalies in the first(second)half of the year in the global average SSS and S1000.The model-simulated variation in SSS is consistent with the observations,but not for S1000,suggesting a substantial uncertainty in simulating and understanding the seasonal variation in subsurface salinity.The CMIP5 and CMIP6 models overestimate the magnitude of the seasonal variation of the SSS in the tropics in the region 20°S-20°N but underestimate the magnitude of the seasonal change in S1000 in the Atlantic and Indian oceans.These assessments show new features of the model errors in simulating ocean salinity and support further studies of the global hydrological cycle.
文摘The Sumampa River in Mampong-Ashanti in Ghana is a very important river that supplies water to the water processing company for treatment for the whole community and its environs. In spite of its importance, the buffer area of the river has been encroached by settlers. Residential houses sited along the river have channeled their waste water into the river and several anthropogenic activities go on along the river. Therefore, this study was conducted to assess the effects of anthropogenic activities on the quality of the river. Water samples were collected from various parts of the river including the source and outflow for physico-chemical and microbial analyses. The results showed that, the water was highly turbid with high total dissolved solids at some points because of intense anthropogenic activities. High turbidity and total dissolved solids greatly influence the microbial load of the water. We therefore recommend that measures are put in place to protect the Sumampa River through the creation of a buffer zone by planting trees along the banks of the river. The trees could help detoxify the run-off water that flows into the river.
文摘‘Selfie’taking was introduced to the common people by smartphones and has become a common practice across the globe in no time.With technological advancement and the popularity of smartphones,selfie-taking has grown rapidly within a short time.In light of the new trend set by the generation,this study aimed to explore reasons for selfie-taking and selfie-posting on social media and their effects on the social and psychological lives of young adults.A purposive sampling method was adopted to select 20 Indian citizens,between 18 and 24 years.The data were collected through semi-structured interviews and analysed using thematic analysis.Selfie-taking and posting on social media give positive feelings,and it acts as a mood modifier dependent mostly on the favourability and feedback about the post which in turn affects emotions and self-satisfaction.
文摘Dealing with kinetic energy is one of the most important problems in hydraulic structures,and this energy can damage downstream structures.This study aims to study energy dissipation of supercritical water flow passing through a sudden contraction.The experiments were conducted on a sudden contraction with 15 cm width.A 30 cm wide flume was installed.The relative contraction ranged from 8.9 to 9.7,where relative contraction refers to the ratio of contraction width to initial flow depth.The Froude value in the investigation varied from 2 to 7.The contraction width of numerical simulation was 5~15 cm,the relative contraction was 8.9~12.42,and the Froude value ranged from 8.9~12.42.In order to simulate turbulence,the k-εRNG model was harnessed.The experimental and numerical results demonstrate that the energy dissipation increases with the increase of Froude value.Also,with the sudden contraction,the rate of relative depreciation of energy is increased due to the increase in backwater profile and downstream flow depth.The experimentation verifies the numerical results with a correlation coefficient of 0.99 and the root mean square error is 0.02.
文摘The potential effect of canopy cover on the quality of River Offin which serves as drinking water for communities including Hwediem, Mprim and Boanim in the Mampong Municipality of the Ashanti region of Ghana was studied. These communities exemplify Ghanaian farming communities. Often, rural farmers do not have access to clean water. Using the part of the river serving these communities as a test case, we assessed the quality of water along a gradient of three different levels of canopy cover (closed, semi-closed and open canopy) where residents frequently access water. Physico-chemical tests showed that, the level of most of the physical and chemical properties of the water under all three different canopy covers was within the acceptable limits set by the World Health Organization. There was low turbidity where the canopy was closed resulting in relatively lower faecal coliforms. Total dissolved solids were also less where canopy cover was closed. Therefore, the general water quality could be potentially improved by planting trees along the river to form canopy.
文摘Long-term, body-adhered medical devices rely on an adhesive interface to maintain contact with the patient. The greatest threat to on-body adhesion is mechanical stress imparted on the medical device. Several factors contribute to the ability of the device to withstand such stresses, such as the mechanical design, shape, and size of the device. This analysis investigates the impact that design changes to the device have on the stress and strain experienced by the system when acted on by a stressor. The analysis also identifies the design changes that are most effective at reducing the stress and strain. An explicit dynamic finite element analysis method was used to simulate several design iterations and a regression analysis was performed to quantify the relationship between design and resultant stress and strain. The shape, height, size, and taper of the medical device were modified, and the results indicate that, to reduce stress and strain in the system, the device should resemble a square in shape, be short in height, and small in size with a large taper. The square shape experienced 17.5% less stress compared to the next best performing shape. A 10% reduction in device height resulted in a 21% reduction in stress and 24% reduction in strain. A 20% reduction in device size caused a 7% reduction in stress and 2% reduction in strain. A 20% increase in device taper size led to a negligible reduction in stress and a 6% reduction in strain. The height of the device had the greatest impact on the resultant stress and strain.
文摘The introduction of invasive insect pests across national borders has become a major concern in crop production. Accordingly, national plant protection organizations are challenge to reinforce their monitoring strategies, which are hampered by the weight and size of inspection equipment, as well as the taxonomic extensiveness of interrupted species. Moreover, some insect pests that impede farmer productivity and profitability are difficult for researchers to address on time due to a lack of appropriate plant protection measures. Farmers’ reliance on synthetic pesticides and biocontrol agents has resulted in major economic and environmental ramifications. DNA barcoding is a novel technology that has the potential to improve Integrated Pest Management decision-making, which is dependent on the ability to correctly identify pest and beneficial organisms. This is due to some natural traits such as phenology or pesticide susceptibility browbeaten by IPM strategies to avert pest establishment. Specifically, Deoxyribonucleic acid (DNA) sequence information was applied effectively for the identification of some micro-organisms. This technology, DNA barcoding, allows for the identification of insect species by using short, standardized gene sequences. DNA barcoding is basically based on repeatable and accessible technique that allows for the mechanisation or automation of species discrimination. This technique bridges the taxonomic bio-security gap and meets the International Plant Protection Convention diagnostic standards for insect identification. This review therefore discusses DNA barcoding as a technique for insect pests’ identification and its potential application for crop protection.
