气象与环境科学
氣象與環境科學
기상여배경과학
METEOROLOGICAL AND ENVIRONMENTAL SCIENCES
2011年
3期
61-66
,共6页
山地%日照时间%数字高程模型%地理信息系统
山地%日照時間%數字高程模型%地理信息繫統
산지%일조시간%수자고정모형%지리신식계통
mountains%sunshine duration%DEM%GIS
基于数字高程模型(DEM)模拟计算了大理州山地日照时间的时空分布,结果显示,除了日照百分率外,坡度、坡向和地形之间的相互遮蔽对日照时间的分布有很大的影响。冬季太阳高度角较小,地形遮蔽对日照时间的影响很大,夏季相对较小。遮蔽系数4月最大,12月最小。一年中的任意时刻随着坡度的增加日照时间减少。坡向对日照时间的影响有很强的季节性:春分和秋分时期南坡与北坡日照时间相等且都为最多,夏至北坡最多,冬至南坡最多;春分至秋分期间,北坡日照时间最多,其余时间南坡日照时间最多,全年日照时间南坡最多。105°和255°坡向的坡面地形遮蔽系数常年都为0.82,不随时间变化。
基于數字高程模型(DEM)模擬計算瞭大理州山地日照時間的時空分佈,結果顯示,除瞭日照百分率外,坡度、坡嚮和地形之間的相互遮蔽對日照時間的分佈有很大的影響。鼕季太暘高度角較小,地形遮蔽對日照時間的影響很大,夏季相對較小。遮蔽繫數4月最大,12月最小。一年中的任意時刻隨著坡度的增加日照時間減少。坡嚮對日照時間的影響有很彊的季節性:春分和鞦分時期南坡與北坡日照時間相等且都為最多,夏至北坡最多,鼕至南坡最多;春分至鞦分期間,北坡日照時間最多,其餘時間南坡日照時間最多,全年日照時間南坡最多。105°和255°坡嚮的坡麵地形遮蔽繫數常年都為0.82,不隨時間變化。
기우수자고정모형(DEM)모의계산료대리주산지일조시간적시공분포,결과현시,제료일조백분솔외,파도、파향화지형지간적상호차폐대일조시간적분포유흔대적영향。동계태양고도각교소,지형차폐대일조시간적영향흔대,하계상대교소。차폐계수4월최대,12월최소。일년중적임의시각수착파도적증가일조시간감소。파향대일조시간적영향유흔강적계절성:춘분화추분시기남파여북파일조시간상등차도위최다,하지북파최다,동지남파최다;춘분지추분기간,북파일조시간최다,기여시간남파일조시간최다,전년일조시간남파최다。105°화255°파향적파면지형차폐계수상년도위0.82,불수시간변화。
This article simulated calculates the spatial and temporal distribution of mountains' sunshine duration in Dali based on the digital elevation model(DEM).The results show besides the percentage of sunshine,slope,aspect and the masking of terrain have a great effect on the distribution of sunshine duration.The solar altitude is smaller in winter,the masking of terrain has a great impact on sunshine duration,but it's smaller relatively in summer.The ratio of masking in April is maximum and in December is minimum all year around.Any time of year with the increase in slope the sunshine duration is reduced.The aspect has a strong seasonal on the sunshine duration: the northern slope and southern slope are equal to a maximum duration of sunshine in vernal equinox and autumnal equinox,the northern slope is maximum in summer solstice and the southern slope is maximum in winter solstice.During the vernal equinox to the autumnal equinox,sunshine duration in the northern slope is maximum,the southern slope is maximum in the rest of time,but the annual sunshine duration is maximum in the southern slope.The ratio of masking terrain in 105 ° and 255 ° of slope is 0.82 all year round,and the ratio is not variable with time.