近50年辽宁无霜期积温时空演变特征

摘要

利用GIS技术对辽宁近50 a不同时间尺度无霜期积温的时空演变特征进行了分析,结果表明:辽宁无霜期积温区域平均值年际变异很大,最大值超过600℃·d,近50 a极显著增多,增幅为85℃·d/10a,主要增多时段在90年代以后;其中增幅最大区域分布在辽西南部和中部平原南部,超过90℃·d/10a,趋势极显著,东部山区西部和辽西西北部增幅最小,在60℃·d/10a以下,增多趋势不显著.气候平均值由南向北呈递减分布,B时段(1971～2000年)与A时段(1961～1990年)相比,东部山区中西部和辽西西部略有减少,东部山区北部、辽西大部、中部平原大部以及大连部分地区增多最多,在60℃·d以上.从年代际变化来看,2 600℃·d以上的积温高值范围由环渤海地区向东北不断扩展,2000年后达到最大,覆盖了辽西大部、中部、辽北大部和辽南大部地区.%Based on the data of daily mean temperature of Liaoning Province in the recent 50 years ( 1961 ～ 2007),and using GIS technique, analysis is made of different time scale of spatio-temporal evolvement characteristics of frostless period accumulated temperature (FIPAT) in Liaoning in recent 50 years. The results demonstrate that in terms of regional average, the FLPAT whose the largest variability is larger than 600℃ .d varies evidently between years and increases significantly with a rate of increase of 85℃·d/10a in recent 50 years and mainly after 1990s. The largest rate above 90℃ .d/10a distributes in the south of west Lianning and south of central plain. The smallest rate below 60℃ .d/10a distributes in most parts of east mountainous area and the west of west Liaoning. The west of east mountainous area and northwest of west Liaoning are the places whére the FLPAT increases unsignificently. Comparing the B period from 1971 ～ 2000 with the A period from 1961 ～ 1990, except for center and west of east mountainous area as well as the west of west Liaoning where the FLPAT decreases slightly, the climatology of the FLPAT which decreases progressively from south above 2 700℃·d to north below I 800℃·d increases in most parts of Liaoning, especially in the north of east mountainous area, most parts of west Liaoning, most parts of cental plain and part of Dalian where the rate of increase of the FLPAT above 60℃·d is the largest. In term of interannual change, the scope area with high value of above 2 600℃·d expands to northeast from surrounding Bohai zone and reaches the peak after 2000, covering middle Liaoning, most parts of west Liaoning and north Liaoning as well as south Liaoning.