Ua ʻike ʻia ʻo ka hapa o nā ao i hoʻopaʻa ʻia i ka hau e pili ana i nā ʻāpana lepo o ke ao e hana nei ma ke ʻano he nuclei no ka hoʻokumu ʻana i ka hau hau. Akā naʻe, ʻaʻole i hōʻike maopopo ʻia me ka hoʻohana ʻana i ka hoʻonohonoho ʻikepili nui. Ma kahi noiʻi i paʻi ʻia ma 31 Iulai 2025, ua hōʻoia nā mea noiʻi i kēia pilina umele 35 makahiki o ka ʻikepili ukali. Ua hōʻike lākou i ka hapa o nā ao hau (viz., ice-to-total frequency a i ʻole ITF) in ka ʻĀkau ʻĀkau ma waena o −15° a me −30°C pili ikaika me ka nui o nā ʻāpana lepo i nā ao. He mea nui kēia no ka hoʻohālike ʻana i ke aniau no ka mea E hoʻopili ʻia ka hoʻoneʻe ʻana a me ka ua o nā ao e ka hau a i ʻole ke ao wai.
Hoʻoulu ka huaʻōlelo "puehu" i ka manaʻo o ka pilikia a me ka hōʻoluʻolu, ʻo ia ka mea no ka mea ʻo ka lepo mai nā kumu kūlohelohe a me nā hana kanaka (e like me ke kūkulu ʻana, nā kaʻina hana, a me ka neʻe ʻana o ke kaʻa) e hāʻawi i nā mea ʻokoʻa i ka ea e alakaʻi ana i ka pollution ea e loaʻa ai ka hopena maikaʻi ʻole i ke olakino a me nā ʻōnaehana cardiovascular. Ma nā ʻāina maloʻo a me nā ʻāina semi-arid, ʻo ke one a me ka ʻino lepo e pahū i ka nui o nā ʻāpana lepo mineral i ka lewa. ʻO ka hopena o ka hoʻohaumia ʻana i ka ea e pili ana i ke olakino lehulehu, ka honua a me ka waihona kālā radiation.
He kuleana koʻikoʻi nō hoʻi ka lepo mineral e ka lewa i ka ʻōnaehana aniau. Hoʻopili a hoʻopuehu ia i ka pāhawewe lā a me ka wela no laila pili pono i ke koena ikehu o ka ʻōnaehana honua. ʻO ka hoʻololi ʻana i ka ukana ʻeleʻele minerala e hoʻololi i ke koena radiation o kahi māhele (ʻo ia hoʻi, ka hoʻololi ʻana i ka neʻe ʻana o ka radiation ma muli o ka lepo a i ʻole ka lepo radiative koi). He mau anoano no ka hookumu ana o ke ao kulu ke komo ka mahu wai maluna o lakou. Ua kapa ʻia ʻo cloud condensation nuclei (CCN), ʻo kēia mau ʻāpana he kumu no nā kulu o ke ao a he mea nui ia no ka hoʻomaka ʻana o ka hoʻokumu ʻana o ka kulu o ke ao a me ka ulu ʻana o nā ao a me ka ua. Hoʻopilikia ʻole ia i ka ʻōnaehana aniau o ka Honua, me ka hoʻoikaika ʻana i ka radiative. He hopena koʻikoʻi ka hoʻololi ʻana i ka ʻike ʻana o nā mea ea ea e like me ka CCN i nā waiwai o ke ao, ka hoʻoneʻe ʻana a me ke aniau.
ʻO nā ʻano ao a me Ice-to-total frequency (ITF)
ʻEkolu mau ʻano o nā ao ma muli o ke ʻano o ka hau hau a i ʻole nā kulu wai wai. Hoʻokumu ʻia nā ao hau me nā kristal hau i hoʻokumu ʻia ma o ka nucleation a puni nā ʻāpana nucleating hau (INP) e like me ka lepo mineral. Hoʻokumu maʻamau lākou ma nā kiʻekiʻe kiʻekiʻe kahi e lanakila ai ka mahana hau. ʻO nā ao wai, ma ka ʻaoʻao ʻē aʻe, ua haku ʻia me nā kulu wai wai a hana ʻia i ka wā e maʻalili ai ka mahu wai i ka lewa a hoʻoheheʻe i loko o nā kulu wai wai a puni ka nuclei condensation cloud (CCN) e like me ka lepo a i ʻole nā mea paʻakai. Loaʻa i nā ao huikau nā hau hau a me nā kulu wai supercooled. ʻO kēia kaʻina hana i ka wā e maloʻo ai nā kulu wai supercooled ma luna o nā kristal hau a i ʻole nā mea hau ʻē aʻe, e piʻi nui ana i ko lākou nuipa a me ka paʻa i kapa ʻia he riming. ʻIke mua ʻia ka hoʻōho ʻana i nā ao huikau i nā mahana ma waena o -5°C a me -25°C ma nā wahi e maloʻo ai nā kulu wai supercooled i ka hui ʻana me nā kristal hau. ʻO ka Ice-to-total frequency (ITF) ka māhele o nā ao hau i hoʻohālikelike ʻia me ka huina o nā ao i ʻike ʻia ma ka pae kiʻekiʻe o ke ao.
Hoʻomaopopo maikaʻi ʻia nā kaʻina hana i ka hopena o ka lepo mineral i ka ʻōnaehana aniau, akā naʻe, aia ma lalo o ʻelua mau pilikia no ka poʻe noiʻi e hoʻoponopono ai.
ʻO ka mea mua, ʻaʻohe kānalua i ka manaʻo ʻana i nā hopena aniau a pololei ʻole o ka lepo mineral ma ka pae honua. ʻO ka misionari EMIT (Earth Surface Mineral Dust Source Investigation) o NASA i kau ʻia ma luna o ka ISS e kamaʻilio i kēia ma ka palapala ʻana i ka lepo lepo mineral o nā ʻāina maloʻo o ka Honua a me ka hāʻawi ʻana i ka ʻikepili honua no ka hoʻohālikelike ʻana i ke aniau. Ua loaʻa iā ia kahi milestone i ka lā 27 Iulai 2022 i ka wā i hāʻawi ai i kāna ʻike mua o ka Honua. I ka makahiki i hala aku nei i ka makahiki 2024, ua hoʻololi ʻo ia i kahi hana misionari lōʻihi a hiki i 2026.
ʻO ka lua, ʻoiai ua ʻike ʻia no ka manawa lōʻihi e pili ana ka hapa o nā ao i hoʻopaʻa ʻia i ka hau i nā ʻāpana lepo i loko o ke ao e hana nei ma ke ʻano he nuclei no ka hoʻokumu ʻana i ka hau hau. Akā naʻe, ʻaʻole i hōʻike maopopo ʻia me ka hoʻohana ʻana i ka hoʻonohonoho ʻikepili nui. Ma kahi noiʻi i paʻi ʻia ma 31 Iulai 2025, ua hōʻoia nā mea noiʻi i kēia pilina me ka hoʻohana ʻana i 35 mau makahiki o ka ʻikepili satellite. Ua hōʻike lākou i ka nui o nā ao i hoʻopaʻa ʻia i ka hau (ʻo ia hoʻi, ʻo ke ao-top ice-to-total frequency a i ʻole ITF) ma ka ʻĀpana ʻĀkau ma waena o −15° a me −30°C pili ikaika me ka nui o nā ʻāpana lepo i loko o nā ao. He mea koʻikoʻi kēia no ka hoʻohālike ʻana i ke aniau no ka mea, e hoʻopili ʻia ka radiative hoʻoikaika a me ka ua o nā ao e ka hau a i ʻole ke ao wai.
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(Hoʻomaikaʻi: Kauka Sachchidanand Singh, Luna ʻepekema Nui, CSIR-NPL, India no kāna mau mea waiwai nui ma ke kumuhana a me ka hoʻoponopono)
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E hoʻomaopopo ':
- Villanueva D., et al 2025. Wehewehe ʻia ka hoʻoheheʻe ʻia ʻana o ka lepo ma luna o ke ao ma ka ʻaoʻao ʻākau. KAUKAU. 31 Iulai 2025. Vol 389, Puka 6759 pp. 521-525. DOI: https://doi.org/10.1126/science.adt5354
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Pākuʻi pili
- Nā hopena o ke aniau o ka lepo minerala o ka lewa: Loaʻa ka Milestone EMIT Mission (1 ʻAukake 2022).
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 in the Northern Hemisphere between −15° and −30°C strongly correlates with the abundance of dust particles in the clouds. This is important for climate modelling because radiative forcing and precipitation of the clouds will be influenced by whether they are topped by a ice or water cloud layer.){kind=link}