Pehea i hoʻokumu ʻia ai nā wao nahele e like me ka ʻike honua
Ua manaʻo pinepine ʻia nā wao nahele he mau ʻāina one ākea, wela, a me ka ʻole o ka ʻāina. Eia nō naʻe, ma ke ʻano honua, ʻaʻole like mau nā wao nahele me ke one, a ʻaʻole hoʻi lākou i wela mau. Aia nā wao nahele pōhaku, nā wao nahele ʻiliʻili, a me nā wao nahele anu a hau hoʻi. ʻO ke kī i ka hoʻomaopopo ʻana i nā wao nahele hoʻokahi mea: maloʻo. Ma ke ʻano laulā, ʻo ka wao nahele kahi wahi i loaʻa ka ua liʻiliʻi loa—ʻoi aku ka liʻiliʻi ma mua o 250 mm i kēlā me kēia makahiki—no laila ʻoi aku ka nui o ka mahu ma mua o ka nui o ka wai e komo ana. No laila, pehea e hana ʻia ai nā wahi e like me kēia? Wehewehe ka honua i ka hoʻokumu ʻia ʻana o ka wao nahele ma o ka hui pū ʻana o nā kaʻina hana lewa, kahi honua, nā ʻano ʻāina, nā au moana, a me ka mōʻaukala honua.
1. Nā wao nahele ma muli o ke kaulike ʻole o ka wai
I ke ʻano honua kino, ua pili ka hoʻokumu ʻia ʻana o ka wao nahele i ke kumumanaʻo o ke kaulike wai. Lilo kahi wahi i wao nahele ke hiki ʻole i ka wai i loaʻa mai ka ua a i ʻole nā kumu ʻē aʻe ke hoʻopau i ka wai i nalowale ma o ka mahu ʻana a me ka transpiration. I loko o nā manawa lōʻihi (nā ʻumi a i nā tausani makahiki), lahilahi nā mea kanu, nalowale ka lepo i ka makū, a hoʻomaka nā kaʻina hana geomorphological maʻamau o nā wahi maloʻo e noho aliʻi. I nā huaʻōlelo ʻē aʻe, hana ʻia nā wao nahele ʻaʻole no ka mea ʻaʻohe wai iki, akā no ka mea ʻo ke aniau a me ka ʻāina e paʻakikī ai ka wai e noho.
2. Ke kuleana o ke kaʻapuni lewa honua: kāʻei kaomi kiʻekiʻe subtropical
ʻO kekahi o nā kumu nui o ka hoʻokumu ʻia ʻana o ka wao nahele a puni ka honua, ʻo ia nā ʻano kaʻapuni ea honua. Aia nā wao nahele nui he nui a puni nā latitudes 20°–30° N/S, e like me ka Sahara, Arabia, a me ke kikowaena o Australia. Aia kēia mau ʻāina ma lalo o ka mana o nā kāʻei kaomi kiʻekiʻe subtropical e pili ana me ke kelepona Hadley.
Penei ke ʻano hana:
– Ma kahi kokoke i ka equator, ikaika ka wela o ka lā a piʻi aʻe ka ea (convection) a hana i nā ao a me ka ua nui.
– ʻO ka ea i nalowale ka mahu wai e neʻe ana i nā subtropics ma nā papa o luna o ka lewa.
– I loko o nā ʻāina subtropics, iho ka ea (subsidence). I ka iho ʻana o ka ea, wela ia ma ke ʻano adiabatically a lilo i maloʻo.
– Ke kāohi nei kēia ea mehana a maloʻo i ka hoʻokumu ʻia ʻana o ke ao, no laila he kakaikahi ka ua.
ʻO kēia ke kumu honua e hana ai nā wao nahele nui he nui i kahi "kāʻei" a puni nā subtropics.
3. Ka mana o nā au anuanu o ke kai: nā wao nahele kahakai noe
Aia nā wao nahele he nui ma nā ʻaoʻao komohana o nā ʻāina nui, e like me ka Wao nahele ʻo Atacama ma Chile a me ka Wao nahele ʻo Namib ma ke komohana o ʻApelika. Hoʻopilikia ʻia kēia mau wahi e nā au kai anuanu (e like me ke Au ʻo Humboldt a me ke Au ʻo Benguela). Hoʻomaʻalili nā au kai anuanu i ka ea ma luna o ka ʻilikai, e hopena ana i:
– Ua hoʻemi ʻia ka mahu ʻana mai ke kai mai.
– Lilo ka ea i paʻa (hoʻohuli ʻia ka mahana) a paʻakikī ke piʻi aʻe e hana i nā ao ua.
– Hoʻokumu pinepine ʻia ka noe a i ʻole nā ao haʻahaʻa ma kahi o ka ua.
ʻO ka hopena, hiki i nā wahi kahakai ke maloʻo loa ʻoiai ko lākou kokoke ʻana i ke kai. Ua ʻike ʻia ʻo Atacama ʻo ia kekahi o nā wahi maloʻo loa ma ka Honua, a ʻaneʻane ʻaʻohe ua o kekahi mau wahi no nā makahiki.
4. Aka ua: wao nahele ma hope o nā mauna
He mea nui nō hoʻi nā kumu ʻāina. Hiki ke hana ʻia nā wao nahele ma muli o ke aka ua. Ke neʻe nā ea pulu i nā mauna:
– Hoʻoikaika ʻia ka ea e piʻi i luna, hoʻomaʻalili, a laila hoʻopūʻiwa a hāʻule i mea ua ma ka ʻaoʻao makani.
– Ma hope o ka hala ʻana i ka piko, iho ka ea ma ka ʻaoʻao hope (leeward), wela, a maloʻo.
– ʻAʻole nui ka ua e loaʻa ana i nā wahi ma ke kua o nā mauna.
ʻO nā laʻana e komo pū ana me nā wahi maloʻo ma hope o nā mauna ʻo Andes (nā ʻāpana o Patagonia), a i ʻole nā wahi maloʻo ma hope o Sierra Nevada, ka mea e hāʻawi ai i nā kūlana semi-arid a i nā wao nahele ma nā ʻāpana o ʻAmelika Hui Pū ʻIa. Hōʻike kēia ʻano hana hiki ke hana ʻia nā wao nahele ma waho o nā subtropics, inā pale nā pale topographic i ka lako o ka mahu wai.
5. Wao nahele ʻāina: mamao loa mai nā kumu mahu wai
Hoʻokumu ʻia kekahi mau wao nahele no ka mea ua mamao loa lākou mai ke kai, no laila ua nalowale ka hapa nui o ko lākou makū i nā ea e hiki aku ana iā lākou. ʻO nā loko nui o ka ʻāina he haʻahaʻa ka ua, ʻoiai inā ua ālai ʻia ka neʻe ʻana o ka ea mai ke kai e nā mauna a i ʻole kekahi mau ʻano makani.
ʻO ka Wao nahele ʻo Gobi ma ʻĀsia kahi laʻana o kahi ʻāina maloʻo i hoʻopili ʻia e ka mamao mai ke kai a me ke ʻano o ka ʻāina. Eia kekahi, ʻike pinepine nā loko o ka ʻāina i nā loli nui o ka mahana: nā lā wela a me nā pō anuanu loa ma muli o ka nele o ka mahu wai a me nā ao, ka mea e kōkua pinepine ai i ka mālama ʻana i ka wela.
6. Wao nahele anu: maloʻo ma nā wahi haʻahaʻa
Ma ke ʻano honua, ua komo pū nā wao akua me nā wao akua anu i loko o nā wao akua. Ua kapa pinepine ʻia ʻo Antarctica ʻo ia ka wao akua nui loa ma ka Honua no ka mea he liʻiliʻi ka ua (ʻo ka hau ka hapa nui). No ke aha e hiki ai i nā wahi anu ke lilo i wao akua?
No ka mea, ʻaʻole hiki i ka ea anuanu ke hoʻopaʻa i ka nui o ka mahu wai, ʻo ka hopena:
– Ua kaupalena ʻia nā ao a me ka ua.
– Haʻahaʻa ka makū o ka lewa.
– He kakaikahi ka hāʻule ʻana o ka hau, ʻoiai hiki ke hōʻiliʻili ka hau no ka mea e lohi ana ka heheʻe ʻana o nā mahana haʻahaʻa loa.
Loaʻa nō hoʻi nā wao nahele anu ma kekahi mau wahi kiʻekiʻe a i ʻole nā latitudes kiʻekiʻe, e like me nā ʻāpana o Asia Waena.
7. Ke kuleana o nā kaʻina hana geomorphological: makani, ʻino, a me nā ʻano ʻāina wao nahele
Ke hoʻokumu ʻia kahi aniau maloʻo, lilo nā kaʻina hana hoʻokumu ʻāina wao nahele i mea nui. ʻO nā mea nui ʻelua, ʻo ia ka makani a me ka ua pōkole.
1. Kaʻina hana Aeolian (makani)
Hiki i ka makani ke lawe i ke one a me ka lepo, e hana ana i:
– Nā puʻu one o nā ʻano like ʻole (barchan, seif, a pēlā aku)
– Nā waihona loess (lepo maikaʻi) ma kekahi mau wahi
– Hoʻokumu ʻia ka ʻino e like me nā pōhaku mushroom ma muli o ka ʻānai ʻana o ke one
2. Kahe wai episodic
ʻOiai ʻaʻole pinepine ka ua, i ka wā e ua ai, he pōkole a ikaika hoʻi. Ma muli o ka paʻakikī o ka lepo maloʻo e omo koke i ka wai, hana ʻia nā kahe wai ikaika a kālai ʻia:
– Wadi (muliwai kau)
– Pā peʻahi Alluvial
– Kahekahe koke
ʻAʻole hana kēia mau kaʻina hana i nā wao nahele i "paʻa," akā, he loli nui i ka wā lōʻihi.
8. Nā kumu hoʻololi o ke aniau a me ka mōʻaukala honua
Hiki ke hoʻololi ʻia ke ʻano o ka wao nahele e ka loli o ke aniau no ka wā lōʻihi, ma ke ʻano kūlohelohe a me ke kanaka. Ma luna o nā tausani a i miliona mau makahiki, hiki i nā loli o nā ʻano makani, nā loli o ka ʻāina, nā loli o ka ʻilikai, a me nā ʻano like ʻole o ke kaʻapuni o ka Honua ke hoʻololi i kahi ʻāina momona i maloʻo, a i ʻole ka ʻaoʻao ʻē aʻe. ʻO ka Sahara, no ka laʻana, ua ʻike ʻo ia i kahi wā "Green Sahara" i ka wā i pulu ai a loaʻa nā loko a me nā mea kanu ākea.
Eia kekahi, aia ke kumumanaʻo o ka neoneo ʻana, ʻo ia ke kaʻina hana o ka hoʻonui ʻana i nā kūlana maloʻo ma muli o ka hui pū ʻana o ka loli o ke aniau a me nā hana a kānaka (ka neoneo ʻana i ka ululāʻau, ka ʻai nui ʻana, a me ka mālama wai maikaʻi ʻole). ʻAʻole ʻo ka neoneo wale nō ke ala e "puka mai ai" nā wao nahele, akā hiki iā ia ke hoʻonui i ka maloʻo a me ka hōʻino ʻāina ma nā wahi semi-arid.
Ka hopena
Wahi a ke ʻano honua, hoʻokumu ʻia nā wao nahele ma muli o nā ʻano aniau e hoʻopuka ana i ka ua haʻahaʻa loa a me ke kaulike wai ʻole. Hiki i kēia mau mea ke komo pū me ke kaʻapuni lewa subtropical, nā au kai anuanu, nā aka ua mauna, ka mamao mai ke kai, a me nā kūlana anuanu e kaupalena ana i ka nui o ka mahu wai. Ma hope o ka hoʻokumu ʻana o nā mea aniau i ka maloʻo, nā kaʻina hana geomorphological—ʻo ia hoʻi ka makani a me ke kahe wai episodic—e hoʻohālikelike i nā hiʻohiʻona ʻokoʻa o ka ʻāina wao nahele. Ma ka hoʻomaopopo ʻana i kēia mau ʻano hana, hiki iā mākou ke ʻike i nā wao nahele ma mua o nā "wahi one" wale nō, akā, ʻo nā ʻōnaehana honua i hoʻohālikelike ʻia e nā pilina paʻakikī ma waena o ka lewa, nā moana, a me ka ʻili o ka Honua.
