1、 Recommendation ITU-R P.1510-1 (06/2017) Mean surface temperature P Series Radiowave propagation ii Rec. ITU-R P.1510-1 Foreword The role of the Radiocommunication Sector is to ensure the rational, equitable, efficient and economical use of the radio-frequency spectrum by all radiocommunication serv
2、ices, including satellite services, and carry out studies without limit of frequency range on the basis of which Recommendations are adopted. The regulatory and policy functions of the Radiocommunication Sector are performed by World and Regional Radiocommunication Conferences and Radiocommunication
3、 Assemblies supported by Study Groups. Policy on Intellectual Property Right (IPR) ITU-R policy on IPR is described in the Common Patent Policy for ITU-T/ITU-R/ISO/IEC referenced in Annex 1 of Resolution ITU-R 1. Forms to be used for the submission of patent statements and licensing declarations by
4、patent holders are available from http:/www.itu.int/ITU-R/go/patents/en where the Guidelines for Implementation of the Common Patent Policy for ITU-T/ITU-R/ISO/IEC and the ITU-R patent information database can also be found. Series of ITU-R Recommendations (Also available online at http:/www.itu.int
5、/publ/R-REC/en) Series Title BO Satellite delivery BR Recording for production, archival and play-out; film for television BS Broadcasting service (sound) BT Broadcasting service (television) F Fixed service M Mobile, radiodetermination, amateur and related satellite services P Radiowave propagation
6、 RA Radio astronomy RS Remote sensing systems S Fixed-satellite service SA Space applications and meteorology SF Frequency sharing and coordination between fixed-satellite and fixed service systems SM Spectrum management SNG Satellite news gathering TF Time signals and frequency standards emissions
7、V Vocabulary and related subjects Note: This ITU-R Recommendation was approved in English under the procedure detailed in Resolution ITU-R 1. Electronic Publication Geneva, 2017 ITU 2017 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without written perm
8、ission of ITU. Rec. ITU-R P.1510-1 1 RECOMMENDATION ITU-R P.1510-1 Mean surface temperature (Question ITU-R 201/3) (2001-2017) Scope Recommendation ITU-R P.1510 contains monthly and annual maps of mean surface temperature that are recommended for the prediction of statistics of different propagation
9、 effects such as rainfall rate, rain attenuation and gaseous attenuation due to water vapour and oxygen. Keywords Temperature, digital maps, ERA Interim The ITU Radiocommunication Assembly, considering a) that information on annual and monthly mean surface temperatures is needed for propagation mode
10、lling purposes; b) that the information is needed for all locations on the surface of the Earth, recommends 1 that the data in Annex 1 be used to obtain the annual and monthly mean surface temperatures when no local data are available. Annex 1 1 Surface mean temperature The monthly mean surface temp
11、erature data, Tii (K), where ii = 01, 02, 03, 04, 05, 06, 07, 08, 09, 10, 11, and 12, at 2 m above the surface of the Earth, are an integral part of this Recommendation and are available as digital maps. The latitude grid is from 90 N to +90 N in 0.75 steps, and the longitude grid is from 180 E to +
12、180 E in 0.75 steps. The annual mean surface temperature data, TAnnual (K) at 2 m above the surface of the Earth are also an integral part of this Recommendation and are available as digital maps. The latitude grid is from 90 N to +90 N in 0.75 steps, and the longitude grid is from 180 E to +180 E i
13、n 0.75 steps. These digital maps are available in the file Rec. P.1510-1 Supplement.zip. The annual mean surface temperature or the monthly mean surface temperature at any desired location at 2 m above the surface of the Earth can be derived according to the following steps: a) determine the four gr
14、id points (Lat1, Lon1), (Lat2, Lon2), (Lat3, Lon3) and (Lat4, Lon4) surrounding the desired location (Lat, Lon); 2 Rec. ITU-R P.1510-1 b) determine the monthly or annual mean surface temperature at 2 m above the surface of the Earth, 1T , 2T , 3T , and 4T at the four surrounding grid points. The lat
15、itude grid is from 90 N to +90 N in 0.75 steps, and the longitude grid is from 180 E to +180 E in 0.75 steps; c) determine T at the desired location (Lat, Lon) by performing a bi-linear interpolation using the four surrounding grid points as described in Annex 1 Paragraph 1b of Recommendation ITU-R
16、P.1144. The monthly mean surface temperature maps have been derived from 36 years (1979-2014) of European Centre of Medium-range Weather Forecast (ECMWF) ERA Interim data, and the annual mean surface temperature map is the average of the monthly mean surface temperature maps weighted by the relative
17、 number of days in each calendar month. For reference, a global map of annual mean surface temperature is shown in Fig. 1. Rec. ITU-R P.1510-1 3 FIGURE 1 Annual mean surface temperature (K) 150030601500960031501530609075454575Latitude () N31010810290300609102108300290280270260250240230Longitude()EP.1510-01
