scholarly journals Climate Trends at a Hotspot of Chronic Kidney Disease of Unknown Causes in Nicaragua, 1973–2014

2021 ◽  
Vol 18 (10) ◽  
pp. 5418
Author(s):  
Zoe E. Petropoulos ◽  
Oriana Ramirez-Rubio ◽  
Madeleine K. Scammell ◽  
Rebecca L. Laws ◽  
Damaris Lopez-Pilarte ◽  
...  
Keyword(s):  
Chronic Kidney Disease ◽  
Kidney Disease ◽  
Weather Data ◽  
Maximum Temperature ◽  
Daily Maximum Temperature ◽  
Daily Maximum ◽  
Climate Trends ◽  
Monthly Average ◽  
Weather Stations ◽  
Maximum Temperatures

An ongoing epidemic of chronic kidney disease of uncertain etiology (CKDu) afflicts large parts of Central America and is hypothesized to be linked to heat stress at work. Mortality rates from CKDu appear to have increased dramatically since the 1970s. To explore this relationship, we assessed trends in maximum and minimum temperatures during harvest months between 1973 and 2014 as well as in the number of days during the harvest season for which the maximum temperature surpassed 35 °C. Data were collected at a weather station at a Nicaraguan sugar company where large numbers of workers have been affected by CKDu. Monthly averages of the daily maximum temperatures between 1996 and 2014 were also compared to concurrent weather data from eight Automated Surface Observing System Network weather stations across Nicaragua. Our objectives were to assess changes in temperature across harvest seasons, estimate the number of days that workers were at risk of heat-related illness and compare daily maximum temperatures across various sites in Nicaragua. The monthly average daily maximum temperature during the harvest season increased by 0.7 °C per decade between 1973 and 1990. The number of days per harvest season with a maximum temperature over 35 °C increased by approximately five days per year between 1974 and 1990, from 32 days to 114 days. Between 1991 and 2013, the number of harvest days with a maximum temperature over 35 °C decreased by two days per year, and the monthly average daily maximum temperature decreased by 0.3 °C per decade. Comparisons with weather stations across Nicaragua demonstrate that this company is located in one of the consistently hottest regions of the country.

scholarly journals Monthly Temperature Observations for Uganda

2013 ◽  
Vol 52 (10) ◽  
pp. 2363-2372 ◽  
Author(s):  
John R. Christy
Keyword(s):  
Time Series ◽  
Public Access ◽  
Maximum Temperature ◽  
Daily Minimum Temperature ◽  
Daily Maximum Temperature ◽  
Daily Maximum ◽  
Record Keeping ◽  
Monthly Average ◽  
Weather Observations ◽  
Temperature Observations

AbstractThe International Surface Temperature Initiative is a worldwide effort to locate weather observations, digitize them for public access, and attach provenance to them. As part of that effort, this study sought documents of temperature observations for the nation of Uganda. Although scattered reports were found for the 1890s, consistent record keeping appears to have begun in 1900. Data were keyed in from images of several types of old forms as well as accessed electronically from several sources to extend the time series of 32 stations with at least 4 yr of data back as far as data were available. Important gaps still remain; 1979–93 has virtually no observations from any station. Because many stations were represented by more than one data source, a scheme is described to extract the “best guess” values for each station of monthly averages of the daily maximum, minimum, and mean temperature. A preliminary examination of the national time series indicates that, since the early twentieth century, it appears that Uganda experienced essentially no change in monthly-average daily maximum temperature but did experience a considerable rise in monthly-average daily minimum temperature, concentrated in the last three decades. Because there are many gaps in the data, it is hoped that readers with information on extant data that were not discovered for this study will contact the author or the project so that the data may be archived.

scholarly journals Frequency of compound hot-dry weather extremes has significantly increased in Australia since 1889

2021 ◽  
Author(s):  
Brian Collins
Keyword(s):  
Temporal Variations ◽  
Nonparametric Tests ◽  
Weather Data ◽  
Maximum Temperature ◽  
Daily Maximum Temperature ◽  
Daily Maximum ◽  
Grid Cells ◽  
Weather Extremes ◽  
Spatial Homogeneity ◽  
Daily Weather Data

There is high confidence that climate change has increased the probability of concurrent temperature-precipitation extremes, changed their spatial-temporal variations, and affected the relationships between drivers of such natural hazards. However, the extent of such changes has been less investigated in Australia. Daily weather data (131 years, 1889-2019) at 700 grid cells (1◦ × 1◦) across Australia was obtained to calculate annual and seasonal mean daily maximum temperature (MMT) and total precipitation (TPR). A nonparametric multivariate copula framework was adopted to estimate the return period of compound hot-dry (CHD) events based on an ‘And’ hazard scenario (hotter than a threshold ‘And’ drier than a threshold). CHD extremes were defined as years with joint return periods of larger than 25 years. Mann-Kendall nonparametric tests was used to analyse trends in MMT and TPR as well as in the frequency of univariate and CHD extremes. A general cooling-wetting trend was observed over 1889-1989. Significant increasing trends were detected over 1990-2019 in the frequency and severity of hot extremes across the country while trends in dry extremes were mostly insignificant (and decreasing). Results showed a significant increase in the association between temperature and precipitation at various temporal scales. The frequency of CHD extremes was mostly stable over 1889-1989, but significantly increased between 1990 and 2019 at 44% of studied grid cells, mostly located in the north, south-east and south-west. Spatial homogeneity (i.e. connectedness) and propagation of extreme events from one grid cell to its neighbouring cells was investigated across Australia. It can be concluded that this connectedness has not significantly changed since 1889.

Effects of patchy shade on stream water temperature: how quickly do small streams heat and cool?

2004 ◽  
Vol 55 (8) ◽  
pp. 737 ◽  
Author(s):  
J. Christopher Rutherford ◽  
Nicholas A. Marsh ◽  
Peter M. Davies ◽  
Stuart E. Bunn
Keyword(s):  
Travel Time ◽  
Dynamic Equilibrium ◽  
Stream Water ◽  
Rate Of Change ◽  
Maximum Temperature ◽  
Daily Maximum Temperature ◽  
Daily Maximum ◽  
Small Streams ◽  
Maximum Temperatures ◽  
Strong Linear Relationship

Summer field observations in five 2nd order streams (width 1–2 m, depth 5–15 cm, velocity 5–10 cm s–1) in Western Australia and south-east Queensland showed that daily maximum temperatures changed by ±4°C over distances of 600–960 m (travel time 2–3 h) immediately downstream from 40–70% step changes in riparian shade. There was a strong linear relationship between the rate of change of daily maximum temperature and the change of shade such that downstream from a 100% change of shade the heating/cooling rates are ±4°C h–1 and ±10°C km–1 (upper bound ±6°C h–1 and ±15°C km–1) respectively. These high rates only apply over short distances and travel times because downstream water temperatures adjust to the new level of shade and reach a dynamic equilibrium. Shade was too patchy in the study streams to measure how long water takes to reach equilibrium, however, using an existing computer model, we estimate that this occurs after ~1200 m (travel time 4 h). Further modelling work is desirable to predict equilibrium temperatures under given meteorological, flow and shade conditions. Nevertheless, landowners and regulators can use this information to determine whether the presence/absence of certain lengths of bankside shade are likely to cause desirable/undesirable temperature decreases/increases.

Prediction of temperatures in cattle dung for estimating development times of coprophilous organisms

1988 ◽  
Vol 78 (2) ◽  
pp. 235-240 ◽  
Author(s):  
J. N. Matthiessen ◽  
M. J. Palmer
Keyword(s):  
Air Temperature ◽  
Meteorological Data ◽  
Maximum Temperature ◽  
Daily Maximum Temperature ◽  
Threshold Temperature ◽  
Cattle Dung ◽  
Daily Maximum ◽  
Daily Minimum ◽  
Maximum Temperatures ◽  
Minimum Air Temperature

AbstractIn studies in Western Australia, temperatures in air and one- and two-litre pads of cattle dung set out weekly and ranging from one to 20 days old were measured hourly for 438 days over all seasons, producing 1437 day x dung-pad observations. Daily maximum temperatures (and hence thermal accumulation) in cattle dung pads could not be accurately predicted using meteorological data alone. An accurate predictor of daily maximum dung temperature, using multiple regression analysis, required measurement of the following factors: maximum air temperature, hours of sunshine, rainfall, a seasonal factor (the day number derived from a linear interpolation of day number from day 0 at the winter solstice to day 182 at the preceding and following summer solstices) and a dung-pad age-specific intercept term, giving an equation that explained a 91·4% of the variation in maximum dung temperature. Daily maximum temperature in two-litre dung pads was 0·6°C cooler than in one-litre pads. Daily minimum dung temperature equalled minimum air temperature, and daily minimum dung temperatures occurred at 05.00 h and maximum temperatures at 14.00 h for one-litre and 14.30 h for two-litre pads. Thus, thermal summation in a dung pad above any threshold temperature can be computed using a skewed sine curve fitted to daily minimum air temperature and the calculated maximum dung temperature.

Rapid Local Urbanization around Most Meteorological Stations Explains the Observed Daily Asymmetric Warming Rates across China from 1985 to 2017

2020 ◽  
Vol 33 (20) ◽  
pp. 9045-9061 ◽  
Author(s):  
Shaojing Jiang ◽  
Kaicun Wang ◽  
Yuna Mao
Keyword(s):  
Large Scale ◽  
Maximum Temperature ◽  
Daily Minimum Temperature ◽  
Daily Maximum Temperature ◽  
Daily Maximum ◽  
Surface Solar Radiation ◽  
Land Cover Data ◽  
Warming Rate ◽  
Observational Bias ◽  
Weather Stations

AbstractThe increasing rate of the observed daily minimum temperature Tmin has been much higher than that of the observed daily maximum temperature Tmax during the past six decades across China. In this study, the local urbanization impact on these observed asymmetric warming rates was investigated. The latest released land-cover data with a 30-m spatial resolution and annual temporal resolution from 1985 to 2017 were used to quantify the urbanization ratios around weather stations. Although urbanized areas occupied only 2.25% of the landmass in China, the percentage of stations with an urbanization ratio over 20% increased from 22.1% to 68.2% during the period 1985–2017. Significant asymmetric warming rates at urban stations were identified, which were approximately 3 times larger compared to the average asymmetry observed at all 2454 stations in China. However, this asymmetry disappeared at rural stations. These differences are mainly due to the rapid local urbanization around most meteorological stations in China since 1985, which affected the spatial representation of observations and led to the observed asymmetry warming rates. The results reported here indicate that the observed asymmetric warming rate over China from 1985 to 2017 is an observational bias due to local urbanization around most stations rather than large-scale climate change. The results also explain the phenomenon that the observed warming rate of Tmin remains higher than that of Tmax after 1990 when the surface solar radiation stops decreasing in China.

scholarly journals Impact of Aligning Climatological Day on Gridding Daily Maximum–Minimum Temperature and Precipitation over Canada

2011 ◽  
Vol 50 (8) ◽  
pp. 1654-1665 ◽  
Author(s):  
Ron F. Hopkinson ◽  
Daniel W. McKenney ◽  
Ewa J. Milewska ◽  
Michael F. Hutchinson ◽  
Pia Papadopol ◽  
...  
Keyword(s):  
Minimum Temperature ◽  
Maximum Temperature ◽  
Daily Minimum Temperature ◽  
Daily Maximum Temperature ◽  
Daily Maximum ◽  
Daily Minimum ◽  
Temperature And Precipitation ◽  
Daily Data ◽  
National University ◽  
Maximum Temperatures

AbstractOn 1 July 1961, the climatological day was redefined to end at 0600 UTC at all principal climate stations in Canada. Prior to that, the climatological day at principal stations ended at 1200 UTC for maximum temperature and precipitation and 0000 UTC for minimum temperature and was similar to the climatological day at ordinary stations. Hutchinson et al. reported occasional larger-than-expected residuals at 50 withheld stations when the Australian National University Spline (ANUSPLIN) interpolation scheme was applied to daily data for 1961–2003, and it was suggested that these larger residuals were in part due to the existence of different climatological days. In this study, daily minimum and maximum temperatures at principal stations were estimated using hourly temperatures for the same climatological day as local ordinary climate stations for the period 1953–2007. Daily precipitation was estimated at principal stations using synoptic precipitation data for the climatological day ending at 1200 UTC, which, for much of the country, was close to the time of the morning observation at ordinary climate stations. At withheld principal stations, the climatological-day adjustments led to the virtual elimination of large residuals in maximum and minimum temperature and a marked reduction in precipitation residuals. Across all 50 withheld stations the climatological day adjustments led to significant reductions, by around 12% for daily maximum temperature, 15% for daily minimum temperature, and 22% for precipitation, in the residuals reported by Hutchinson et al.

scholarly journals Trends in Weather Conditions and Performance by Age Groups Over the History of the Berlin Marathon

2021 ◽  
Vol 12 ◽  
Author(s):  
Beat Knechtle ◽  
David Valero ◽  
Elias Villiger ◽  
José R. Alvero-Cruz ◽  
Pantelis T. Nikolaidis ◽  
...  
Keyword(s):  
Environmental Conditions ◽  
Atmospheric Pressure ◽  
Age Groups ◽  
Maximum Temperature ◽  
Daily Maximum Temperature ◽  
Daily Maximum ◽  
Age Group ◽  
Impaired Performance ◽  
Marathon Race ◽  
Maximum Temperatures

The effect of different environmental conditions such as temperature, wind, barometric pressure, and precipitation has been well investigated in elite marathoners, but not by age categories (i.e., age group marathoners). The aim of the study was to investigate the potential influence of environmental conditions such as temperature, precipitation, and atmospheric pressure on marathon performance in age group marathoners competing in the ‘Berlin Marathon’ from 1974 to 2019. A total of 869,474 valid finisher records were available for analysis, of which 711,136 correspond to males and 158,338 to females. The influence of temperature, atmospheric pressure, and precipitation on marathon race times was investigated in age group marathoners grouped in 5-year-intervals. Within the 46 years of Berlin marathons under investigation, there was some level of precipitation for 18 years, and 28 years without any rain. Sunshine was predominant in 25 of the events, whilst in the other 21 years, cloud cover was predominant. Marathon race times were significantly and positively correlated with age (i.e., older runners were slower than younger runners) where the correlation was higher for males than for females. Marathon race times were significantly and positively correlated with both the hours of sunshine and the daily maximum temperature. The fastest marathon runners (meaning the minimum times) achieved the fastest race times on race days with higher maximum temperatures (i.e., 15–30°C). Daily maximum temperatures showed an influence on age group marathoners from age group 35–40 years and older. Higher precipitation levels impaired performance across most age groups. In summary, higher daily maximum temperatures (i.e., >15°C) and higher precipitation levels impaired performance of master marathoners (i.e., 35–40 years and older) competing in the ‘Berlin Marathon’ in the last 45 years. Master marathoners should start in marathon races with temperatures < 15°C and no precipitation in order to achieve a fast marathon race time.

scholarly journals Trends of the daily maximum temperatures in relation with the climatic change and the urbanization in the Athens basin

2013 ◽  
Vol 8 (3) ◽  
pp. 186-194
Keyword(s):  
Time Series ◽  
Comparative Study ◽  
Statistical Significance ◽  
Extreme Temperature ◽  
Maximum Temperature ◽  
Daily Maximum Temperature ◽  
Societal Implications ◽  
Daily Maximum ◽  
Time Period ◽  
Maximum Temperatures

It is well known that the studies that associate the climatic changes with the greenhouse effect, as a sequence of uninterruptedly ongoing figures in the concentration mainly of carbon dioxide, have been focused on the trends of the mean temperature. On the other hand the variability and the trends of the extreme temperature values have not been considered sufficiently. We notice that the variability of the maximum and minimum temperature values and generally of the extreme weather has direct economic and societal implications. The interest in this paper is focused on the study of the trends of the daily and the monthly maximum temperature during the warm months July and August for the time period from 1955 to 2000 in the wide Athens area and specifically measurements of the Nea Philadelphia and Helliniko meteorological stations. Nea Philadelphia represents an immiscibly urban area station, while Helliniko a coastal suburban area one. The specific sites were selected for the comparative study of the temperature maximum trends in a time period which covers the population growth in the area of Athens. For the whole time period, the differences of the daily maximum temperature from the corresponding 10-days period mean maximum temperatures per month were calculated for each site. Then, the days with positive difference per month and per year as well as the trends of the time-series for each station were recorded along with the statistical significance of the regression slope’s value using the Student t-test distribution. Furthermore, in order to identify the “warmest decade” in the time-series, a study of the daily maximum temperature trend for the months July and August was performed for each decade followed by a test for the statistical significance of the slope coefficient. It is known that the presumable differences of the temperature time-series depend on the influence of the urbanization, the modification of the natural suburban environment and / or on the stations’ displacement. Based on these facts, we present more in this paper the conclusions of a comparative study of the results regarding each station analytically as well as the interpretation of the results concerning all the stations as an ensemble.

scholarly journals On forecasting daily summer maximum temperature at Madras

MAUSAM ◽  
2021 ◽  
Vol 49 (1) ◽  
pp. 95-102
Author(s):  
Y. E. A. RAJ
Keyword(s):  
Zonal Wind ◽  
Lead Time ◽  
Optimal Number ◽  
Maximum Temperature ◽  
Daily Maximum Temperature ◽  
Statistical Techniques ◽  
Daily Maximum ◽  
Skill Scores ◽  
Summer Maximum ◽  
Maximum Temperatures

Forecasting schemes based on statistical techniques have been developed to forecast daily summer (March-May) maximum temperatures of Madras. A set of optimal number of predictors were chosen from a large number of parameters by employing stepwise forward screening. Separate forecasting schemes for Madras city and airport, with lead time of 24 and 9 hr were developed from the data of 12 years and tested in an independent sample of 4 years. Maximum temperature of the previous day, normal daily maximum temperature, temperature advection index and morning zonal wind at Madras at 900 hPa level were among the predictors selected. The schemes yielded good results providing 77-87% correct, forecasts with skill scores of 0.29-0.57.

scholarly journals Lyapunov Exponents and Temperature Transitions in a Warming Australia

2019 ◽  
Vol 32 (10) ◽  
pp. 2969-2989 ◽  
Author(s):  
Stephen Gilmore
Keyword(s):  
Lyapunov Exponents ◽  
Heat Waves ◽  
Maximum Temperature ◽  
Daily Maximum Temperature ◽  
Daily Maximum ◽  
Temperature Record ◽  
Maximum Daily Temperature ◽  
State Variable ◽  
Abrupt Changes ◽  
Maximum Temperatures

Abstract Multiple potential tipping points in the Earth system that involve alternative states have been identified that are susceptible to anthropogenic forcing. Past events—from millions of years ago to within the last century—have manifest as abrupt changes in climatic indicators such as the temperature record. Recent unprecedented heat waves in Australia, their associated devastation, and the considerations above provide motivation to ask whether the Australian daily maximum temperature record has been subject to such abrupt changes. Using a new diagnostic tool—the Lyapunov plot—here it is shown that multiple temperature transitions have occurred with respect to the maximum daily temperature record in widely separated locations in Australia over the last 150 years. All maximum Lyapunov exponents are positive in sign, indicating that the transitions are chaos-to-chaos transitions, and that the different climate modes identified are likely to be manifestations of distinct chaotic attractors. Many of these events occur simultaneously with transitions or extremes in the major natural cycles affecting Australia’s climate, but this observation is not universal. It is known that chaos-to-chaos transitions can result in changes in the value(s) of the state variable(s) that can range from subtle to severe. Although the identified transitions are not catastrophic, this observation does not rule out the possibility of severe, unprecedented, and discontinuous increases in average daily maximum temperatures occurring in Australia at any time within the next few decades.

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