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Extremely high land surface temperatures affect soil ecological processes, alter land‐atmosphere interactions, and may limit some forms of life. Extreme surface temperature hotspots are presently identified using satellite observations or deduced from complex Earth system models. We introduce a simple, yet physically based analytical approach that incorporates salient land characteristics and atmospheric conditions to globally identify locations of extreme surface temperatures and their upper bounds. We then provide a predictive tool for delineating the spatial extent of land hotspots at the limits to biological adaptability. The model is in good agreement with satellite observations showing that temperature hotspots are associated with high radiation and low wind speed and occur primarily in Middle East and North Africa, with maximum temperatures exceeding 85°C during the study period from 2005 to 2020. We observed an increasing trend in maximum surface temperatures at a rate of 0.17°C/decade. The model allows quantifying how upper bounds of extreme temperatures can increase in a warming climate in the future for which we do not have satellite observations and offers new insights on potential impacts of future warming on limits to plant growth and biological adaptability. Plain Language Summary: While satellite imagery can identify extreme land surface temperatures, land and atmospheric conditions for the onset of maximum land surface temperature (LST) have not yet been globally explored. We developed a physically based analytical model for quantifying the value and spatial extent of maximum LST and provide insights into combinations of land and atmospheric conditions for the onset of such temperature extremes. Results show that extreme LST hotspots occur primarily in the Middle East and North Africa with highest values near 85°C. Importantly, persistence of surface temperatures exceeding 75°C limits vegetation growth and disrupts primary productivity such as in Lut desert in Iran. The study shows that with global warming, regions with prohibitive land surface temperatures will expand. Key Points: Hotspots for high land surface temperatures (LSTs) were globally identified using a physically based analytical approach incorporating land and atmospheric conditionsHigh LSTs primarily occur in Middle East and North Africa with values exceeding 85°CMaximum LSTs rising at a rate of 0.17°C/decade may limit plant growth and biological adaptability in a warming world [ABSTRACT FROM AUTHOR]

Hydraulic fracturing can be utilized to extract trapped hydrocarbon where integrated fracture networks do not exist for sufficient production. In this work, design parameters of a hydraulic acid fracturing of a tight carbonate reservoir in the Middle East were optimized. The effect of optimized hydraulic fracturing on production performance and rate was investigated. Using the petrophysical well logs, formation integrity tests, core data the Mechanical Earth Model (MEM) of the tight carbonate reservoir was created, which resulted in rock mechanical properties and in-situ stresses. The other required parameters for fracturing design were either measured or found from empirical correlations. Following a candidate selection of suitable layers for fracturing, the input parameters were loaded in GOHFER software to design and optimize the fracturing job. Finally, the production forecast was performed and compared with current conditions. The injection parameters (flow rate, total volume, and number of stages) of the fracturing fluid (composed of guar and CMHPG and polymer with 15% HCL acid) were optimized to reach optimum resultant fracture geometry. Finally, optimized injection parameters were found at the injection flow rate of 18 barrels per minute, total injection volume of 90 K-gal, and three stages of injection. Using the optimal injection parameters, the optimized fracture geometrical sizes were determined: the fracture half-length (Lf): 148 m (486 ft), fracture height (Hf) of 64 m (210 ft) and fracture width (Wf) of 0.0962 in. Finally, the effect of this stimulation method on future production performance was investigated. The well production rate showed an increase from 840 STB/Day (before fracturing) to 1270 STB/Day (post fracturing). This study contributes to the practical design and optimization of hydraulic fracturing in the tight carbonate formation of the investigated oilfield and the other potential fields in the region. The results showed that this stimulation method can efficiently improve production performance from reservoir formation. [ABSTRACT FROM AUTHOR]