Bangladesh is susceptible to climate change, thus a detailed study, including the analyses of trends, sub-trends, extreme events and indices was conducted to obtain a complete picture of the climate ...change pattern in Bangladesh utilizing daily rainfall, maximum, minimum and average temperature data of 26 stations from 1975 to 2019 using R 4.0.2 software. For the trend analysis Mann Kendal (MK), modified Mann Kendall (mMK), Innovative Trend Analysis (ITA) and Sen’s slope methods were used. Sub-trend analysis was conducted using ITA. Standard Anomaly Index (SAI) has been used to identify the frequency and severity of extreme events. ClimPACT2 software was used to check the homogeneity and calculate the extremes of temperature and rainfall data. Our analysis showed that during the last four decades, climate variables changed their patterns and trend heterogeneously over Bangladesh. Most stations showed decremental rainfall trend when central part of the country showed a substantial decrease. The northern and central parts of the country showed significant growth of trend for annual average temperature. The temperature in the monsoon season increased, whereas those in dry season decreased. The rainfall and maximum temperature were inversely related during monsoon whereas during dry season both of them decrease. The pre-monsoon and post-monsoonal rainfall also showed decreasing trends, indicating prevailing drought conditions especially in northern and central parts of the country. The SAI analysis showed alternating drought and wet years in almost all the stations. In the past 20 years, the country’s western region experienced more drought years than before whereas the coastal region experienced more wet years. The analysis of climate extreme indices suggests that, Consecutive Dry Days (CDD), Hot Days (TX90P) and Hot Nights (TN90P) show significant increasing trend throughout the country. The agricultural productivity, water resource management and food security are anticipated to benefit from this study.
•Comprehensive study of the climate change pattern of entire Bangladesh.•Climate variables changed their patterns and trends heterogeneously over Bangladesh during the last four decades.•Decremental rainfall trend was found in majority stations.•Alternating drought and wet year were found in almost all the stations.•The extreme indices related to temperature showed more statistically significant results.
Objective
To measure the extent to which the provision of mammograms was impacted by the COVID‐19 pandemic and surrounding guidelines.
Data Sources
De‐identified summary data derived from medical ...claims and eligibility files were provided by Independence Blue Cross for women receiving mammograms.
Study Design
We used a difference‐in‐differences approach to characterize the change in mammograms performed over time and a queueing formula to estimate the time to clear the queue of missed mammograms.
Data Collection
We used data from the first 30 weeks of each year from 2018 to 2020.
Principal Findings
Over the 20 weeks following March 11, 2020, the volume of screening mammograms and diagnostic mammograms fell by 58% and 38% of expected levels, on average. Lowest volumes were observed in week 15 (April 8 to 14), when screening and diagnostic mammograms fell by 99% and 74%, respectively. Volumes began to rebound in week 19 (May), with diagnostic mammograms reaching levels to similar to previous years’ and screening mammograms remaining 14% below expectations. We estimate it will take a minimum of 22 weeks to clear the queue of missed mammograms in our study sample.
Conclusions
The provision of mammograms has been significantly disrupted due to the COVID‐19 pandemic.
In this article, the meridional gradient of daily potential vorticity (PV) on the 330 K isentropic surface is used to identify atmospheric blocking events for the period 1979–2019. The associated ...two‐dimensional index considers not only Rossby wave breaking, but also energy dispersion and nonlinearity of blocking systems, and thus has a solid theoretical foundation. It also has the advantage of automatically excluding subtropical high‐pressure systems in summer and autumn. The index reveals that the Northern Hemisphere exhibits high blocking frequency over Euro‐Atlantic, North Pacific and Greenland in winter, spring and autumn, and over two wide‐extended bands at high latitudes in summer. Two prominent blocking episode (BE) intensity centres are found over the eastern Atlantic and eastern Pacific in all seasons, while the long‐lived BE is primarily situated in regions with high BE frequency. There is more frequent and longer‐lived BE in the Euro‐Atlantic sector than in the North Pacific, whereas the BE in the North Pacific is more intense. Notably, with the same poleward criterion for the four seasons, the BE frequency and duration are supposed to be overestimated in summer. Comparing our blocking detection method with previous blocking indices provides additional information about the long‐term trends for blocking frequency and intensity, which can be useful to our understanding of future extremes on climate time‐scales. It is found that both blocking frequency and intensity exhibit upward linear trends in the Ural region and Barents–Kara Sea in winter, Europe, northern North Pacific and East Siberia in spring, western Greenland in summer, as well as Norwegian Sea, Europe and North Atlantic in autumn, which point to increases in high‐impact weather events in these regions.
This is the graphical of Bidimensional climatology and trends of Northern Hemisphere blocking utilizing a new detection method, authored by Muyuan Li, Dehai Luo*, Ian Simmonds, Yao Yao and Linhao Zhong. We devised a new blocking detection method based on the meridional PV gradient to identify two‐dimensional blocking. The climatologies of blocking frequency, intensity and duration are compared with those of previous blocking indices, and the long‐term trends of blocking frequency and intensity suggest regions with more high‐impact weather events.
The climatology of earth's Na density over Fort Collins, CO (41°N, 105°W) based on nocturnal Na lidar observations between 1990 and 1999 was reported by She et al. (2000, ...https://doi.org/10.1029/2000gl003825). Based on a continued 28‐year data set between 1990 and 2017 with the latter part observed over Logan, UT (42N, 112W), we update the seasonal variations between 80 and 110 km. This data set is also used to deduce long‐term responses of Na density (profile) between 75 and 110 km, showing a positive linear trend between 75 and 93 km (with maximum ∼2.87 × 108 m−3/decade at 87 km); it turns negative before approaching zero at 110 km (with minimum ∼−2.96 × 107 m−3/decade at 100 km). The associated solar response is also positive for the altitude range in question (with maximum ∼5.20 × 106 m−3/SFU at 91 km). We also derived the 28‐year mean Na layer column abundance, centroid altitude, and root mean square width to be 3.92 ± 2.14 1013 m−2, 91.3 ± 1.0 km, and 4.62 ± 0.56 km, respectively, and deduced long‐term trend and solar cycle responses of column abundance and centroid altitude, respectively to be 7.81 ± 1.63%/decade and 16.9 ± 2.8%/100SFU, and −355 ± 35 m/decade and −1.94 ± 0.69 m/SFU. We explained conceptually how positive long‐term responses in Na density led to positive responses in column abundance and negative responses in centroid altitude.
Key Points
Based on 28 years (1340 nights) lidar observation at midlatitude, we report monthly mean Na density profiles between 80 and 110 km
This data set showed a positive linear trend between 75 and 93 km with a maximum at 87 km and positive solar response with a maximum at 91 km
The deduced long‐term solar response of column abundance and centroid linear trend are 16.9 ± 2.8%/100SFU and −355 ± 35 m/decade
Droughts have destructive impacts on crop yields and water supplies, and researching droughts is vital for societal stability and human life. This work aimed to assess the spatiotemporal evolution of ...droughts in mainland China over 1961–2013 using four drought indices. These indices were the percentage of precipitation anomaly (Pa), standard precipitation index (SPI), standard precipitation evapotranspiration index (SPEI) and evaporative demand drought index (EDDI) at multiple timescales ranging from 1-week to 24-month. The variations of the SPI, SPEI and EDDI were compared with historical severe or extreme droughts. The general increases of the Pa, SPI and SPEI, and general decrease of the EDDI, consistently implied an overall relief of drought conditions over 1961–2013. The different drought indices revealed historical drought conditions, including the national extreme droughts in 1961, 1965, 1972, 1978, 1986, 1988, 1992, 1994, 1997, 1999 and 2000, but various drought severity levels were classified for each drought event since the classification standards differed. Although the SPI and SPEI performed better than the EDDI and there were higher correlations between the SPI and the SPEI, all the indices were regional- or station-specific and have identified historical severe or extreme drought events. At shorter timescales, the EDDI revealed earlier onsets and ends of flash droughts, unlike those indicated by the SPI and SPEI. The comparison of the different indices based on the historical drought events confirmed the uses of the Pa, SPI and SPEI for determining continuous droughts and that of the EDDI for identifying flash droughts.
Display omitted
•The Pa, SPI, SPEI and EDDI consistently implied an overall relief of drought conditions.•Droughts evolutions were site-, regional-specific and complicated although relieved in recent 53years in mainland China.•The Pa, SPI and SPEI are used for determining continuous droughts and EDDI for identifying flash droughts.
ABSTRACT
The objectives of this study were to investigate the trend in annual precipitation, sunshine duration, wind speed (u
2), and annual and monthly minimum temperature (T
min), maximum ...temperature (T
max), and relative humidity (RH) and the adaptation strategies for the Senegal River Basin. Annual precipitation, T
min, T
max, RH, sunshine duration, and u
2 for the period of 1950–2000 recorded at St‐Louis, Bakel, Dagana, Fanaye, Podor, and Matam have been analysed using the Mann–Kendall test and Sen's slope estimator. Annual precipitation varied with location from 900 mm registered in 1967 at Bakel to 32 mm obtained at Dagana in 1986. A significant decreasing trend (p < 0.001) in precipitation was observed at Podor, Dagana, Matam, Bakel, and St‐Louis. A non‐significant decreasing trend in annual precipitation was observed at Fanaye Dieri. There was a significant increasing trend (p < 0.001) in T
max and T
min at all locations. Sunshine duration had a significant decreasing trend at Podor, Matam, and St‐Louis at the rate of 0.27, 0.28, and 0.35 h decade−1, respectively. RH and u
2 have differences in their trends, with the first one showing a strong and significant decrease and u
2 with less significance in their trends. The trend analysis in the climate variables revealed a change in climate that necessitates some specific actions for resources management sustainability and conservation.
Given that gasoil plays a crucial role in carbon emission reduction, in this paper we propose a time-frequency-based interval decomposition ensemble (TFIDE) learning approach to forecast gasoil ...prices and capture the nonlinear impact of the global trend of low-carbon development on gasoil prices. The proposed method integrates bivariate empirical mode decomposition (BEMD), an interval multilayer perceptron (IMLP) network and a threshold autoregressive interval (TARI) model. First, we use BEMD to decompose interval-valued weekly gasoil prices into a finite number of complex-valued intrinsic mode function (IMF) components and a residual component. Second, we apply the IMLP model to forecast the IMFs and the TARI model to predict the residual part with predictors of carbon reduction technology and carbon emission concerns. After that, we combine all the forecasting results to generate the final gasoil price interval forecasting results. Our empirical results show that our carbon reduction technology variable improves middle-frequency IMF forecasting and that carbon emission concerns have a nonlinear impact on long-term gasoil price intervals. Furthermore, the proposed TFIDE approach outperforms other competing methods under different accuracy measurements.
•We propose a time-frequency-based interval decomposition ensemble (TFIDE) method.•The TFIDE method better captures the complex features of interval-valued gasoil price.•The TFIDE method integrates global carbon factors into the framework, enhancing forecasting and revealing carbon concern's nonlinear impact on gasoil prices.•The TFIDE method is more reliable and robust than other benchmark models.
Five extreme precipitation indicators were calculated on an annual basis for 1890 through 2013 and analysed to determine spatial patterns and temporal trends in the frequency and magnitude of ...observed extreme precipitation events in Kansas located in the central United States. Indicators were selected from the list of the World Meteorological Organization–Commission for Climatology (WMO–CCL) and the Research Programme on Climate Variability and Predictability (CLIVAR). The indicators included the number of days with precipitation greater than or equal to 10 mm/day (R10), maximum number of consecutive dry days (CDD; days with precipitation lower that 1 mm), maximum 5‐day precipitation total (R5D), and simple daily intensity index (SDII) which is the annual precipitation total divided by number of days with precipitation greater than or equal to 1 mm, and the fraction of annual total precipitation due to events exceeding the 95th percentile (R95T) based on the period 1961–1990. Positive trends in the results were found for a majority of stations for R10, R5D, SDII, and R95T. Consecutive dry days was the only index that had a negative trend at a majority of stations. Spatial pattern analysis indicates greater changes in frequencies and magnitudes for eastern Kansas. Results from this study highlight observed climate shifts in precipitation patterns with a tendency towards greater and more frequent extreme precipitation in eastern Kansas and a tendency towards drier conditions in western Kansas. These hydroclimatic adjustments can produce costly impacts in areas that include flood management, hydraulic structures, water availability throughout the year, agricultural production, ecosystems, and human health.
Results from five extreme precipitation indicators highlight observed climate shifts in precipitation patterns with a tendency towards greater and more frequent extreme precipitation in eastern Kansas and a tendency towards drier conditions in western Kansas. The increasing trends for the wet condition indicators, particularly in the eastern Kansas, emphasize the necessity to update water management techniques and maintain water control structures adequately in a variable and changing climate. Western Kansas is faced with prolonged strings of dry weather and a lack of enough water in the growing season has resulted in water withdrawals from underground resources.
Objectives The purpose of this study was to quantify the trends in blood pressure (BP), and the prevalence, awareness, management, and control of hypertension in U.S. adults (≥20 years of age) from ...1999 to 2010, and to assess the efficacy of current clinical measures in diagnosing and adequately treating hypertensive patients. Background Hypertension is a major independent risk factor for cardiovascular disease and stroke. Recent data indicate a decreasing trend in hypertension prevalence, along with improvements in hypertension awareness, management, and control. Methods The study used regression models to assess the trends in hypertension prevalence, awareness, management, and control from 1999 to 2010 among 28,995 male and female adults with BP measurements from a nationally representative sample of the noninstitutionalized U.S. population (National Health and Nutrition Examination Survey NHANES 1999 to 2010), with special attention given to 5,764 participants in NHANES 2009 to 2010. Results In 2009 to 2010, the prevalence of hypertension was 30.5% among men and 28.5% among women. The hypertension awareness rate was 69.7% (95% confidence interval CI: 62.0% to 77.4%) among men and 80.7% (95% CI: 74.5% to 86.8%) among women. The hypertension control rate was 40.3% (95% CI: 33.7% to 46.9%) for men and 56.3% (95% CI: 49.2% to 63.3%) for women. From 1999 to 2010, the prevalence of hypertension remained stable. Although hypertension awareness, management, and control improved, the overall rates remained poor (74.0% for awareness, 71.6% for management, 46.5% for control, and 64.4% for control in management); worse still, no improvement was shown from 2007 to 2010. Conclusions From 1999 to 2010, prevalence of hypertension remained stable. Hypertension awareness, management, and control were improved, but remained poor; nevertheless, there has been no improvement since 2007.
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