Modelling and Forecasting the Impact of Air Temperature on Global Warming: Karachi as a Case Study

Abstract The world has experienced extreme climate changes and global warming. It also causes high temperature, droughts, rising sea level and flooding. In Karachi, the construction activities and transportation caused most of the Green House Gases (GHG) and carbon dioxide (CO2) emission. In the paper, the data under consideration is 60 years mean monthly maximum and minimum air temperature of Karachi ranging from 1961 to 2020 has been used to forecast the temperature impact over time. The minimum and maximum temperature data were observed, forecasted city temperature. ARMA (p, q) model used to modelling and forecasting the behaviour of Karachi maximum and minimum air temperature using Pakistan Metrological Department (PMD) data. The results show that the Theil’s U-Statistics values of each month lie approaches to zero shows that the air temperature is strongly correlated to previously observed values. The results of this study are very beneficial for observing the influence of air temperature on the global warming.

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Increase in Air Temperature in The Region of South Sumatra Province as the Indicator of Global Warming and the Effect on Transpiration of Lansium domesticum Corr.

10.31220/osf.io/jrf35 ◽

2019 ◽

Author(s):

Ari Sugiarto ◽

Hanifa Marisa ◽

Sarno

Keyword(s):

Global Warming ◽

Air Temperature ◽

Transpiration Rate ◽

Temperature Increase ◽

Secondary Data ◽

Temperature Data ◽

Randomized Design ◽

Maximum Air Temperature ◽

Lansium Domesticum ◽

Minimum Air Temperature

Abstract Global warming is one of biggest problems faced in the 21st century. One of the impacts of global warming is that it can affect the transpiration rate of plants that °Ccur. This study purpose to see how much increase in air temperature that occurred in the region of South Sumatra Province and to know the effect of increase in ari temperature in the region of South Sumatra Province on transpiration rate of Lansium domesticum Corr. This study used a complete randomized design with 9 treatments (22.9 °C, 23.6 °C, 24.6 °C, 26.3 °C, 27 °C, 27.8 °C, 31.7 °C, 32.5 °C, and 32.9 °C) and 3 replications. Air temperature data as secondary data obtained from the Meteorology, Climatology and Geophysics Agency (MCGA) Palembang Climatology Station in South Sumatra Province. The measurement of transpiration rate is done by modified potometer method with additional glass box. The data obtained are presented in the form of tables and graphs. Transpiration rate (mm3/g plant/hour) at temperture 22.9 °C = 4.37, 23.6 °C = 7.03, 24.6 °C = 8.03, 26.3 °C = 10.11, 27 °C = 13.13, 27.8 °C = 17.87, 31.7 °C = 23.21, 32.5 °C= 25.45 and 32.9 °C= 27.24. At the minimum air temperature in the region of South Sumatra Province there is increase in air temperature of 1.5 °C, average daily air temperature increase 1.3 °C and maximum air temperature increase 1.2 °C.

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Heatwaves during low tide are critical for the physiological performance of intertidal macroalgae under global warming scenarios

Scientific Reports ◽

10.1038/s41598-020-78526-5 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Marta Román ◽

Salvador Román ◽

Elsa Vázquez ◽

Jesús Troncoso ◽

Celia Olabarria

Keyword(s):

Global Warming ◽

Iberian Peninsula ◽

Air Temperature ◽

Sublethal Effects ◽

Seawater Temperature ◽

Critical Factor ◽

Physiological Performance ◽

Air Temperatures ◽

Cystoseira Tamariscifolia ◽

The Impact

AbstractThe abundance and distribution of intertidal canopy-forming macroalgae are threatened by the increase in sea surface temperature and in the frequency and intensity of heatwaves caused by global warming. This study evaluated the physiological response of predominant intertidal macroalgae in the NW Iberian Peninsula (Bifurcaria bifurcata, Cystoseira tamariscifolia and Codium tomentosum) to increased seawater temperature during immersion and increased air temperatures during consecutive emersion cycles. We combined field mensuration and laboratory experiments in which we measured mortality, growth, maximum quantum yield and C:N content of the macroalgae. Air temperature was a critical factor in determining physiological responses and survivorship of all species, whereas high seawater temperature had sublethal effects. Cystoseira tamariscifolia suffered the greatest decreases in Fv/Fm, growth and the highest mortality under higher air temperatures, whereas C. tomentosum was the most resistant and resilient species. Two consecutive cycles of emersion under atmospheric heatwaves caused cumulative stress in all three macroalgae, affecting the physiological performance and increasing the mortality. The potential expansion of the warm-temperate species B. bifurcata, C. tamariscifolia and C. tomentosum in the NW Iberian Peninsula in response to increasing seawater temperature may be affected by the impact of increased air temperature, especially in a region where the incidence of atmospheric heatwaves is expected to increase.

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Prediction of maximum or minimum air temperature in a coastal location in West Bengal

MAUSAM ◽

10.54302/mausam.v64i4.750 ◽

2021 ◽

Vol 64 (4) ◽

pp. 671-680

Author(s):

SUKUMAR LALAROY ◽

SANJIB BANDYOPADHYAY ◽

SWETA DAS

Keyword(s):

Solar Radiation ◽

Air Temperature ◽

Minimum Temperature ◽

West Bengal ◽

Global Solar Radiation ◽

Maximum Temperature ◽

Accurate Estimation ◽

Radiation Data ◽

Sunshine Hour ◽

Minimum Air Temperature

bl 'kks/k i= dk mÌs'; Hkkjrh; rVh; LFkku vFkkZr~ if'peh caxky ds vyhiqj ¼dksydkrk½ esa izsf{kr HkweaMyh; lkSj fofdj.k dh enn ls gjxzhCl fofdj.k QkWewZyk ls rkjh[kokj la'kksf/kr KRS irk djuk gS ftlls fd vkxs ;fn U;wure rkieku ¼Tmin½ Kkr gks rks vf/kdre rkieku ¼Tmax½ dk iwokZuqeku nsus esa vFkok blds foijhr] mi;ksx fd;k tk ldsA HkweaMyh; lkSj fofdj.k ds chp lglaca/k dh x.kuk rkjh[kokj fd, x, /kwi ds ?kaVkokj vk¡dM+ksa ds vkSlr ds mi;ksx ftlesa vkaXLVªkse izsLdkWV QkewZyk ls izkIr fu;rkad as = 0-25 vkSj bs = 0-5 gS] ls dh xbZZ gSA blesa izsf{kr fd, x, HkweaMyh; lkSj fofdj.k vkadM+ksa dk v/;;u fd;k x;k gSA ;g fuf'pr :i ls dgk tkrk gS fd vkaxLVªkse izsldkWV QkewZyk HkweaMyh; lkSj fofdj.k dk lVhd vkdyu djrk gS vkSj ;g lgh ik;k tkrk gSA bl 'kks/k i= esa gjxzhCl fofdj.k QkewZyk ¼ftles KRS = 0-19 fy;k x;k gS½ ls rkjh[kokj izkIr fd, x, vf/kdre rkiekuksa rFkk U;wure rkiekuksa ds vkSlr ¼vkadM+s Hkkjr ekSle foKku foHkkx ds vyhiqj] dksydkrk ftyk & 24 ijxuk ds dk;kZy; ls izkIr½ dk mi;ksx djds HkweaMyh; lkSj fofdj.k ds chp lglaca/k dh x.kuk dh xbZ gS vkSj bldk v/;;u izsf{kr HkweaMyh; lkSj fofdj.k ds lkFk Hkh fd;k x;k gSA rkjh[kokj la'kksf/kr KRS dh x.kuk gjxzhCl fofdj.k QkewZyk ls dh xbZA blesa HkweaMyh; lkSj fofdj.k ds izsf{kr vkadM+ksa] rkjh[kokj vf/kdre rkiekuksa vkSj U;wure rkiekuksa ds vkSlr mi;ksx esa fy, x, gSaA bls fdlh LVs'ku ds vf/kdre rkiekuksa vkSj U;wure rkieku vkadMksa ds rkjh[kokj KRS ds mi;ksx ds }kjk vkl ikl ds {ks=ksa ds ok"iksRltZu ds fy, HkweaMyh; lkSj fofdj.k dk vkdyu djus ds fy, Hkh mi;ksx esa yk;k tk ldrk gSA The objective of this study is to find the date wise corrected KRS from the Hargreaves Radiation formula with the help of observed global solar radiation for the Indian coastal location namely Alipore (Kolkata) in West Bengal so that subsequently it can be used for predicting maximum temperature Tmax if minimum temperature Tmin is known or vice-versa. The correlation between the global solar radiation calculated by using date wise average sunshine hour data with constants as = 0.25 and bs = 0.5, from Angstrom Prescott formula with the observed global solar radiation data was studied. The assertion that the Angstrom Prescott formula gives nearly accurate estimation of global solar radiation has been found to be correct. Correlation between the global solar radiation calculated by using date wise average of Tmax and Tmin (sourced from IMD located at Alipore, Kolkata, District - South 24 parganas) from Hargreaves Radiation formula (taking KRS = 0.19 ) with the observed global solar radiation data was also studied. Date wise corrected KRS by Hargreaves Radiation formula was computed using the observed data of global solar radiation, date wise average of maximum temperature Tmax and minimum temperature Tmin. The date wise corrected KRS can be used for better prediction of Tmax and Tmin. Also it can be used for estimation of global solar radiation for reference evapo-transpiration of the neighbourhood areas by utilizing the date wise KRS with the Tmax and Tmin of the station.

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Time series analysis of observed maximum and minimum air temperature at four urban cities of India during 1951-2015

MAUSAM ◽

10.54302/mausam.v71i1.6 ◽

2021 ◽

Vol 71 (1) ◽

pp. 57-68

Author(s):

PRAMANIK SAIKAT ◽

SIL SOURAV ◽

MANDAL SAMIRAN

Keyword(s):

Time Series ◽

Power Spectrum ◽

Air Temperature ◽

India Meteorological Department ◽

Wavelet Power Spectrum ◽

Maximum Temperature ◽

Coastal Cities ◽

Increasing Trend ◽

Two Peaks ◽

Minimum Air Temperature

A sixty - five year (1951-2015) long data for monthly minimum temperature (TMIN) and maximum temperature (TMAX), observed by the India Meteorological Department (IMD), is statistically analyzed at four urban stations namely Bhubaneswar, Delhi, Mumbai and Chennai of India. A bimodal nature in seasonality is noticed for TMAX and TMIN at all locations. Two peaks for TMAX and TMIN are observed in May and September. Exceptionally, Mumbai shows TMAX peaks during May and November and Delhi shows TMIN peaks during June and September. Higher standard deviations (SD) for TMAX is noted at Delhi with a maximum in March (1.78 °C), while for Chennai, the SD for TMIN is lesser compared to other cities. Two different periods 1951-1980 (P1, the first half of the study period) and 1981-2015 (P2, the second half of the study period) were identified from the time series of both TMAX and TMIN. A higher increasing trend is observed during P2 than P1 in all the cities except in TMIN at Mumbai. The highest increasing trend (0.040 °C/year) is observed for TMIN in Mumbai during P1 time, but the trend is almost constant (0.001 °C/year) during P2 time. The highest increasing trend for TMIN at Mumbai is mainly contributed by the increasing trend in post-monsoon and winter months in P1. Surprisingly, in both P1 and P2, the trends are less during monsoon months for all the cities. A consistent 5-year (3-year) band is observed throughout the wavelet power spectrum at the coastal cities Bhubaneswar, Mumbai (Chennai). However, the 5-year signal is not consistent at Delhi and it is observed only during the year 1975-1980. The global wavelet power spectrum showed that TMIN at Chennai has less power (0.6 °C2) corresponding to 3-year signal and Mumbai has highest power (12 °C2) corresponding to the 5-year signal in comparison to other cities.

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Evaluating the Impact of the Morphological Transformation of Urban Sites on the Urban Thermal Microenvironment

Buildings ◽

10.3390/buildings8120182 ◽

2018 ◽

Vol 8 (12) ◽

pp. 182 ◽

Cited By ~ 2

Author(s):

Salman Ali ◽

Baofeng Li

Keyword(s):

Air Temperature ◽

Ambient Air ◽

Google Earth ◽

Simulation Software ◽

Maximum Temperature ◽

Urban Site ◽

Rapid Urbanization ◽

Ambient Air Temperature ◽

Morphological Transformations ◽

The Impact

Tropical cities currently face issues of climate change resulting from rapid urbanization and the impact of urban morphological transformations on the microclimate. The analysis of urban physical forms and patterns is a realisticmethodfor quantifying these impacts. This work examined the impact of morphological transformations of an urban site in Wuhan, China, on the microthermal environment at different time periods. We also quantified and compared the impact of four urban site morphologies on ambient air temperature. The morphological changes of the study site were inferred from Google Earth images acquired at different time points in 2006 and 2013. ENVI-met simulation software was used to compare the changes in temperature at the selected site by specific date. The year- and time-based analysis of existing urban morphologies and their impact on the microurban thermal environment shows that the overall minimum and maximum values of morning and afternoon ambient air temperature are nearly the same for the 2013 and 2006 morphologies. The maximum temperature difference was observed in the afternoon (14:00), with an average difference of approximately 2 °C in the east. The findings of this research could provide a useful guide for optimizing the transformation of urban site planning and design and a suitable method for assessing the impact of built-up areas on the environment.

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

Bulletin of Entomological Research ◽

10.1017/s0007485300013006 ◽

1988 ◽

Vol 78 (2) ◽

pp. 235-240 ◽

Cited By ~ 4

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.

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MAKING LEARNING MEDIA FOR GREENBOX EFFECT SIMULATOR TO IMPROVE UNDERSTANDING OF THE CONCEPT OF THE GREENHOUSE EFFECT

JHSS (JOURNAL OF HUMANITIES AND SOCIAL STUDIES) ◽

10.33751/jhss.v5i1.3198 ◽

2021 ◽

Vol 5 (1) ◽

pp. 11-16

Author(s):

Noer Sarifah Ainy ◽

Nestiyanto Hadi

Keyword(s):

Carbon Dioxide ◽

Global Warming ◽

Greenhouse Gases ◽

Air Temperature ◽

Greenhouse Effect ◽

Independent Variables ◽

Carbon Dioxide Gas ◽

The Earth ◽

Yellow Color ◽

Carbon Dioxide Co2

The earth is experiencing global warming due to an increase in air temperature (greenhouse effect). This is due to the large number of greenhouse gases produced by human activities. In addition, it is also due to the reduced number of plants that absorb greenhouse gases, especially carbon dioxide. This condition causes the study of the greenhouse effect to become an object studied by students at school. Understanding the greenhouse effect is somewhat difficult if only understood in theory. Increasing understanding can be done by making practicum learning media. This study aims to create learning media for the Greenbox Effect Simulator to help understand the concept of the greenhouse effect. The research was conducted using control variables and independent variables (use of plants and without plants). The plants used are Caisim, Sri Gading and Anggrek. The presence of carbon dioxide (CO2) greenhouse gases can be detected by three things, namely changes in the color of the CO2 indicator, changes in temperature, and visibility of the box. The color of the CO2 indicator shows green and green yellow for Box B (with plants) which means the concentration of CO2 in normal conditions. Whereas Box C (without plants) gives a yellow color, which means that the concentration of CO2 is at high conditions. The presence of carbon dioxide gas from combustion will increase the temperature by 1.4 - 1.9 oC in Box C (without plants) and 0.7 - 1.5 oC in Box B (use of plants). The visibility of Box B shows a higher brightness level than Box C. The best plants that can absorb CO2 concentrations are orchids. The ability of orchids to absorb CO2 is assisted by their roots which also function to carry out photosynthesis. The existence of plants functions to absorb CO2 quite well when viewed from changes in temperature, color indicators and visibility.

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Estimating the Impact of Global Warming on Aircraft Takeoff Performance in China

Atmosphere ◽

10.3390/atmos12111472 ◽

2021 ◽

Vol 12 (11) ◽

pp. 1472

Author(s):

Wei Yuan ◽

Panxi Dai ◽

Mengxiang Xu ◽

Wei Song ◽

Peng Zhang

Keyword(s):

Global Warming ◽

Critical Temperature ◽

Carrying Capacity ◽

East China ◽

Maximum Temperature ◽

Daily Maximum Temperature ◽

Daily Maximum ◽

Climate Projections ◽

West China ◽

The Impact

Aviation operations are significantly affected by weather conditions, such as high-temperature days. Under global warming, rising temperatures decrease the air density and thus, reduce the maximum takeoff weight of an aircraft. In this study, we investigate the impact of global warming on the aircraft takeoff performance in 53 airports in China by combining observational data and CMIP6 climate projections. There is a distinct geographic inhomogeneity of critical temperature, above which the takeoff weight decreases significantly with the increasing air temperature, mostly due to differences in airport elevations. By the end of the century, under the SSP5-8.5 scenario (with average warming of 5.2 °C in China), the daily maximum temperature for nearly all summer days in West China and for about half of the summer days in East China exceeds critical temperature, indicating that frequent weight restriction will be necessary. We further examine the reduction in carrying capacity due to climate change. By the end of the century, under the SSP5-8.5 scenario, the summer total carrying capacity will be reduced by about 2.8% averaged over all 53 airports. The impacts on airports in West China are nearly four times greater than those in East China, due to the higher vulnerability and stronger warming in West China.

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The Impact of Covid-19 Lockdown on the Urban Micro-Climate of Major Coastal vs Inland Cities of India

10.5194/egusphere-egu21-10790 ◽

2021 ◽

Author(s):

Sutapa Bhattacharjee ◽

Rishikesh Bharti

Keyword(s):

Air Temperature ◽

Land Surface ◽

Longwave Radiation ◽

Peripheral Region ◽

Maximum Temperature ◽

Temperature And Precipitation ◽

Rain Events ◽

The Individual ◽

The Impact ◽

The City

The climatic or meteorological characteristics over a city is significantly influenced by the city dynamics resulting in evolution of a typical micro-climatic condition enveloping the city and peripheral region. The shrinkage and expansion of the urban boundary layer depends on the dimension, design and functioning of a city and its physiographic setup. The lockdown that was enforced for varying durations globally to restrict the Covid-19 pandemic gave an extraordinary opportunity to understand the urban micro-climatic systems with substantially reduced urban operations. Therefore, the present study aims to evaluate the nature of temperature and precipitation conditions for 6 major cities in India, primarily accentuated by the urban fabric and design; during the strict as well as phased lockdown period in India (April &#8211; June, 2020). The principal objective of the study is to determine if moderation in transportation as well as commercial and industrial activities which are considered as the backbone of a metropolitan, can regulate the micro-climatic system it emanates. A comparative analysis has been attempted between the three coastal (Mumbai, Chennai, Kolkata) and three inland (Delhi, Hyderabad, Bangalore) cities to gather an understanding of the impact-magnitude, the sea has on urban meteorology. Meteorological reanalysis, satellite as well as in-situ Automatic Weather Station data products have been used for the analysis and validation of results. During the month of April when the lockdown was most stringent, there was an evident improvement in air quality with decrease in the concentration of PM2.5, PM10 and AOD (Aerosol Optical Depth) for all the cities in a range of 30 &#8211; 60 percent. To examine the direct and indirect impact of the decreased levels of air pollution on the shortwave as well as longwave radiation responsible for creating the UHI effect as well as abnormal rainfall intensity; the air temperature, land surface temperature (LST) and total amount of rainfall received by the individual cities on a daily as well as hourly basis have been considered. The study reveals that there is notable difference in LST and air temperature in the inland cities during the said period in comparison to the previous years, with relative decrease in both minimum and maximum temperature and significant increase in the number of days with lower temperatures. The pattern of high intensity rain events which is typical to intensive urbanization also experienced definite transformation in Bangalore and Delhi even during the phased lockdown period. However, the modification in all these meteorological parameters were observed to be relatively less significant in case of the coastal cities which solidifies the prominence of coastal influence in such metropolis. Therefore, the study concludes that the rapid strengthening of urban micro-climate and its consequences can be mitigated by implementing strategic reduction in core urban activities, especially for cities without external physiographic influence.

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Late 20th century increase in northern Svalbard glacier-derived runoff tracked by encrusting coralline algae

10.5194/egusphere-egu2020-3053 ◽

2020 ◽

Author(s):

Steffen Hetzinger ◽

Jochen Halfar ◽

Zoltan Zajacz ◽

Marco Möller ◽

Max Wisshak

Keyword(s):

Global Warming ◽

Air Temperature ◽

Surface Air Temperature ◽

High Arctic ◽

Climate System ◽

Coralline Algae ◽

The Arctic ◽

Surface Ocean ◽

The Impact ◽

Arctic Surface

The Arctic cryosphere is changing at a rapid pace due to global warming and the large-scale changes observed in the Arctic during the past decades exert a strong influence throughout the global climate system. The warming of Arctic surface air temperatures is more than twice as large as the global average over the last two decades and recent events indicate new extremes in the Arctic climate system, e.g. for the last five years Arctic annual surface air temperature exceeded that of any year since 1900 AD. Northern Spitsbergen, Svalbard, located in the High Arctic at 80&#176;N, is a warming hotspot with an observed temperature rise of ~6&#176;C over the last three decades indicating major global warming impacts. However, even the longest available datasets on Svalbard climatic conditions do not extend beyond the 1950s, inhibiting the study of long-term natural variability before anthropogenic influence. Ongoing climate trends strongly affect the state of both glaciers and seasonal snow in Svalbard. Modeled data suggest a marked increase in glacier runoff during recent decades in northern Svalbard. However, observational data are sparse and short and the potential effects on the surface ocean are unclear. This study focuses on the ultra-high-resolution analysis of calcified coralline algal buildups growing attached to the shallow seafloor along Arctic coastlines. Analysis of these new annually-layered climate archives is based on the long-lived encrusting coralline algae Clathromorphum compactum, providing a historic perspective on recently observed changes. Here, we present a 200-year record of past surface ocean variability from Mosselbukta, Spitsbergen, northern Svalbard. By using algal Ba/Ca ratios as a proxy for past glacier-derived meltwater input, we investigate past multi-decadal-scale fluctuations in land-based freshwater contributions to the ocean surface layer. Our records, based on multiple coralline algal specimens, show a strong and statistically significant increasing trend in algal Ba/Ca ratios from the 1990s onwards, suggesting a drastic increase in land-based runoff at Mosselbukta. The drastic rate of increase is unprecedented during the last two centuries, directly capturing the impact of amplified surface air temperature warming on coastal high Arctic surface ocean environments.&#160;

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