عدم قطعیت مقادیر شدت-فراوانی بارش‌های حداکثر در اثر تغییر اقلیم آتی (مطالعه موردی: استان خراسان رضوی)

نوع مقاله : مقاله پژوهشی

نویسنده

استادیار/ دانشکده مهندسی عمران، دانشگاه صنعتی جندی شاپور

چکیده

گرمایش جهانی خصوصیات بارش‌های حدی را دستخوش تغییراتی خارج از دامنه تغییرات درونی اقلیم کرده است. در این تحقیق تحلیلی از نحوه تغییر مقادیر شدت-مدت-فراوانی بارش(IDF) تحت 10 سناریوی اقلیمی مشتق شده از مدل‌های اقلیم جهانی و سناریوی انتشار A1B برای دوره 2040- 2021 در استان خراسان رضوی ارائه شده است. مقادیر IDF برای 23 ایستگاه مورد بررسی تحت سناریوهای اقلیمی آینده در 3 سطح ریسک (25%، 50% و 75%) توسط یک روش ترکیبی پیشنهادی شامل: (1) تصویر سازی سناریوی بارش روزانه آتی توسط یک مدل ریزمقیاس نمایی ناپارامتریک توسعه داده شده برای مناطق خشک و نیمه خشک، (2) استخراج مقادیر IDF براساس روابط چندک-فراوانی بارش بین بارش‌های ساعتی و روزانه در ترم سری‌های حداکثر سالانه، برآورد شده‌اند. نتایج نشان می‌دهد که شدت بارش‌ها در سطح ریسک 50% نسبت به دوره پایه 2012-1993 بین 23-% تا 3/7% تغییر خواهد کرد. در این بین تداوم‌های کمتر نسبت به بیشتر دامنه تغییرات مثبت تری داشته و در دوره‌‌های بازگشت بالاتر دامنه تغییرات وسیعتر خواهد بود. بطور کلی مناطق مرکزی و جنوبی افزایش کمتری را نسبت به نواحی شمالی استان شاهد خواهند بود. همچنین مناطق پرباران شدت سیل خیزی بیشتری را پیش رو خواهند داشت؛ و در مقابل مناطق کم باران کاهش شدیدتری را متحمل می‌شوند. درسطوح ریسک کم نیز مقادیر شدت‌های حداکثر در آینده افزایش خواهد یافت؛ که این موضوع باید در طراحی سازه‌های پراهمیت مورد توجه خاص قرار گیرد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Uncertainty of extreme rainfall intensity and frequency under future climate change impact: Khorasan-Razavi province

نویسنده [English]

  • H. Seyed Kaboli
Assistant Professor, Department of Civil Engineering, Jundi Shapur University of Technology, Dezful, Iran
چکیده [English]

Global Warning has caused the characteristics of extreme rainfall changed out of range of the internal variability of climate. In this research, an analysis is presented from how variation in intensity, Duration-and Frequency (IDF) of rainfall under 10 climate scenarios derived climate models and A1B emission scenario for 2021-2040 periods in Khorasan-Razavi province. The IDF values for 23 raingage have projected under future climate scenarios in 3 risk levels (25%, 50% and 75%) by a proposed combined approach include: (1) Develop a nonparametric downscaling model to projection of future daily rainfall in arid and semi-arid regions, (2) Establishing frequency-quantile relationships between the t-hour and daily rainfall based annual maximum for estimating the IDF values. Under risk level 2, the results show a wide range of between -23% to +7.3% in rainfall intensity than baseline (1993-2012). The short-duration rainfalls change in more positive range then long-durations; and for return periods of more than 10-year, the range of changes will be wide in this area. Generally, central and southern regions will be received slight increase than northern regions. Also, the high rainfall regions will be ahead a more severe flooding, while the low rainfall regions will be suffered a more severe decrease. Also, in low risk level, rainfall intensity will be increased in the future period; it can be warning to design hydraulic infrastructures with high emphasis.

کلیدواژه‌ها [English]

  • Climate change
  • Extreme rainfall
  • Khorasan-Razavi
  • Uncertainty
  • Downscaling
Abbaspour KC, Faramarzi M, Ghasemi SS, Yang H (2009) Assessing the impact of climate change on water resources in Iran. Water Resources Research 45:10434
Arnbjerg-Nielsen K (2006) Spatial and temporal variation of extreme rainfall significant climate change of extreme rainfall in Denmark. Water Science and Technology 54:1–8
Goyal M K, Burn DH, Ojha CSP (2013) Precipitation simulation based on k-nearest neighbour approach using gamma kernel. ASCE Journal of Hydrologic Engineering 18(5):481-487
Helfer F, Lemckert C, Zhang H (2012) Impacts of climate change on temperature and evaporation from a large reservoir in Australia. Journal of Hydrology 475:365–378
Intergovernmental Panel on Climate Change (IPCC) (2007) The physical science basis—summary for policy makers. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Intergovernmental Panel on Climate Change, Geneva
Madsen H, Arnbjerg-Nielsen K, Mikkelsen PS (2009) Update of regional intensity–duration–frequency curves in Denmark: Tendency towards increased storm intensities. Atmospheric Research 92(3):343-349
Mailhot A, Duchesne S, Caya D, Talbot G (2007) Assessment of future change in intensity-duration-frequency (IDF) curves for southern Quebec using the Canadian Regional Climate Model (CRCM). Journal of Hydrology 347:197-210
Nguyen VTV, Chaleeraktrgkoon C (1990). Estimation of hourly rainfall distribution based on available daily rainfall data. Journal of American Water Recourse Association 11:67–76
Nguyen VTV, Pandey GR (1994) Estimation of short-duration rainfall distribution using data measured at longer time scales. Water Science Technology 29(1):39–45
Nguyen VTV, Nguyen TD, Wang H (1998) Regional estimation of short duration rainfall extremes. Water Science Technology 37(11):15–19
Onof C, Arnbjerg-Nielsen K (2009) Quantification of anticipated future changes in high resolution design rainfall for urban areas. Atmospheric Research 92:350–363
Pagliara S, Viti C, Gozzini B, Meneguzzo F, Crisci A (1998) Uncertainties and trends in extreme rainfall series in Tuscany, Italy: Effects on urban drainage networks design. Water Science and Technology 37(11):195-202
Seyedkaboli H, Akhondali AM, Massahbavani A, Radmanesh F (2012) A downscaling modeling based on K-Nearest Neighbor (K-NN) non-parametric method. Journal of Water and Soil 26(4):779-808 (In Persian)
Sharif M, Burn DH (2006) Simulating climate change scenarios using an improved K-Nearest Neighbor model. Journal of Hydrology 325:179-196
Simonovic SP, Peck A (2009) Updated rainfall intensity duration frequency curves for the City of London under the changing climate. Water Resources Research, Report no. 065, Facility for Intelligent Decision Support, Department of Civil and Environmental Engineering, London, Ontario, Canada, 64p
Simonovic SP, Li L (2003) Methodology for assessment of climate change impacts on large-scale flood protection system. ASCE Journal of Water Resources Planning and Management, 129 (5):361–372.
Singh VP, Zhang L (2007) IDF Curves Using the Frank Archimedean Copula. ASCE Journal of Hydrology Engineering 12(6):651
Solaiman TA, Simonovic SP (2011a) Quantifying uncertainties in the modelled estimates of extreme precipitation events at upper Thames river basin. Water Resources Research, Report no. 067, Facility for Intelligent Decision Support, Department of Civil and Environmental Engineering, London, Ontario, Canada, 64 p
Solaiman TA, Simonovic SP (2011b) Development of probability based intensity-duration-frequency curves under climate change. Water Resources Research, Report no. 072, Facility for Intelligent Decision Support, Department of Civil and Environmental Engineering, London, Ontario, Canada, 94 p
Wu SJ, Tung YK, Yang JC (2005) A simple model to estimate hourly rainfall DDF relationships by incorporating daily rainfall. In Proc., 31st IAHR Congress, Korea Water Resources Association, Seoul, Korea, 3698–3708
Wu SJ, Tung YK, Yang JC 2009. Incorporating daily rainfall to derive at-site hourly depth-duration-frequency relationships. ASCE Journal of Hydrology Engineering 14(9):992-1001