here in catmandu请问这首诗什么意思

here in catmandu请问这首诗什么意思
We have climbed the mountain.There's nothing more to do.It is terrible to come downTo the valleyWhere,amidst many flowers,One thinks of snow,As formerly,amidst snow,Climbing the mountain,One thought of flowers,Tremulous,ruddy with dew,In the valley.One caught their scent coming down.It is difficult to adjust,once down,To the absense of snow.Clear days,from the valley,One looks up at the mountain.What else is there to do?Prayer wheels,flowers!Let the flowersFade,the prayer wheels run down.What have they to doWith us who have stood atop the snowAtop the mountain,Flags seen from the valley?It might be possible to live in the valley,To bury oneself among flowers,If one could forget the mountain,How,never once looking down,Stiff,blinded with snow,One knew what to do.Meanwhile it is not easy here in Katmandu,Especially when to the valleyThat wind which means snowElsewhere,but here means flowers,Comes down,As soon it must,from the mountain.My question is :what's the theme.Short into one sentence.Help me please,thank you =]