Spatial Analysis of the Spatial Variations of Monthly Cooling Degree Days of Iran

Author(s):
Message:
Abstract:
Introduction
Whereas contemporary ecology mental (thinking) space has been filled by global warmness subject, there are a little literature that has been demonstrated day degree mechanisms trend discussion. Global warmness and its effects on human societies are one of the apprehensive subject that this warmness is the result of the hothouse (greenhouse) effect (Zangou et al, 2008). Day degree is the existent difference between the average weather temperature and selective temperature threshold, snow melting, freezing weather, plant growth, blossoming, products harvest, consumption energy for metropolis warmness and coldness and transportation systems that all of them are related to the relative value of these upermeasurments. (Kedia Glouseen 1999, Rahmano et al 2010, Jiango et al 2009) selective temperature thresholds for calculating coldness day degree trend is according to the specific purposes. For an example selective day degree for human relaxation is 18 degree.
Materials And Methods
In this research for investigating (researching) in monthly trend gradient and trend of day degree, the coldness day degree with 25 degree temperature threshold, the daily temperature average during 44 years statistical periods (1340-1383) has been extracted from Sfazar data base. Coldness day degree data with cells 15*15 kilometer were mediated for all of the Iran, that its yield was a matrix by dimension 7187*44 (time * cells). Finally by the help of Mann-Kendall non parameter test, test trend and gradient the total trend for coldness day degree were calculated for every cells. The used software included Matlab and Surfer:a) First based on statistical the differences between observations calculate, one by one. (Raining, temperature, or any other ecological parameter).b) b) And n=the total observation that xj and xk respectively are the series j and k amounts. The above output function make every series sign clear as followed.After determining the sign the Variance of every observation will be calculated by the followed formulation the amount of observation should be higher than 10(n>10).c) The followed stage is Z statistical calculation. Discussion and
Results
Researching (investigating) the coldness trend in Iran territory represent the needs positive trend of coldness in summer and spring season. According to the figure 1 most of regions that have the same trend in the first 6 month of the year their trends are positive. In Farvardin and Ordibehesh months the internal hollowes, forests and southern coast (shores) exept for Oman Sea shore strip by having 45 percentage of Iran extent have the coldness needs positive trend. In Khordad months some strips of southern Zagros slope, the west of Kermanshah, Moghan plain and the east of Oroumieh Lake will add to these regions. By beginning of summer season coldness needs positive trend will represent in half of the country that its maximum location in Shahrivar month will be by 62 percentage of Iran territory. Most of regions that in the spring and summer seasons month have this trend their trend gradient are positive and their rate is 0 to 2 degree of day degree in the year and it means that for this rate in the year their coldness need will be increased. In Ordibehesht the quantitative maximum of the positive trend gradient belongs to the Post-coast of Oman Sea, Lout block medium, and Khouzestan plain by having 24 percentage of region extent and have the positive trend by 2-4 day degree in the year. In Khordad month by adding plain desert and Persian Gulf’s west shores, 29 percentage of country have the positive trend gradient (2- 4 day degree). In summer season observe intensive warmness trend in the middle of Lout and Kahnouj block as positive trend gradient of coldness needs of these regions is 4-6 day degree in the year.
Results
According to the positive trend and increasing the needs of Coldness in internal hollowes and forests and southern shores and as in Shahrivar month more than 60percent of country extent was witness of increasing trend of coldness could point out to being the more warmness of other Iran regions and shortend of autumn season. This is itsef represent the increasing the trend of temperature in ratio to temperature threshold (25 degree).The coldness needs negative trend in summer season in half of the west shahrekord and Khoramabad the west half of Birjand, the north of Sanandaj and Zanjan and east half of the Tehran give glad tidings the coolness trend of these regions. The most rate of trend gradient in year months is positive and is as the rate 0 to 2 day degree in the year. The coldness needs positive trend in the half of the year in the southern strip of the country and internal hollowes confirm the country warm regions temperature is increasing. 2 statement and contemporary outlook of study The warm regions of country have the increasing trend that cause to increasing energy consumption for coldness and energy consumption decreasing for warmness. Coldness needs negative trend in some of the high regions of country the coolness of temperature show to us the coolness of temperature in the mountain strip of country.
Language:
Persian
Published:
Journal of Climate Research, Volume:3 Issue: 12, 2013
Page:
1
magiran.com/p1414107  
دانلود و مطالعه متن این مقاله با یکی از روشهای زیر امکان پذیر است:
اشتراک شخصی
با عضویت و پرداخت آنلاین حق اشتراک یک‌ساله به مبلغ 1,390,000ريال می‌توانید 70 عنوان مطلب دانلود کنید!
اشتراک سازمانی
به کتابخانه دانشگاه یا محل کار خود پیشنهاد کنید تا اشتراک سازمانی این پایگاه را برای دسترسی نامحدود همه کاربران به متن مطالب تهیه نمایند!
توجه!
  • حق عضویت دریافتی صرف حمایت از نشریات عضو و نگهداری، تکمیل و توسعه مگیران می‌شود.
  • پرداخت حق اشتراک و دانلود مقالات اجازه بازنشر آن در سایر رسانه‌های چاپی و دیجیتال را به کاربر نمی‌دهد.
In order to view content subscription is required

Personal subscription
Subscribe magiran.com for 70 € euros via PayPal and download 70 articles during a year.
Organization subscription
Please contact us to subscribe your university or library for unlimited access!