Statistical processing of pollutant concentration projections

Abstract

Je oc ̌eka ́va ́no, z ̌e se v troposfe ́r ̌e zme ̌nı ́ mnoho faktoru ̊ a procesu ̊ vlivem probı ́hajı ́cı ́ch klimaticky ́ch zme ̌n. Tyto zme ̌ny pravde ̌podobne ̌ ovlivnı ́ rez ̌im koncentracı ́ troposfe ́ricky ́ch la ́tek. V pr ̌ı ́pade ̌ ozonu je situace svy ́m zpu ̊sobem nejista ́, nebot ' tyto oc ̌eka ́vane ́ zme ̌ny majı ́ c ̌asto protichu ̊dny ́ u ́c ̌inek na jeho produkci a za ́nik. K projektova ́nı ́ jeho budoucı ́ch koncentracı 'se pouz ̌ı ́vajı ́chemicko-klimaticke ́ modely, ktere ́ ale obvykle vykazujı 'systematicke ́ chyby s pu ̊vodem v mnoha ru ̊zny ́ch zdrojı ́ch. Ac ̌koliv existujı ́ statisticke ́ na 'stroje, ktere ́ lze pouz ̌ı ́t ke kompenzaci te ̌chto nedostatku ̊, c ̌asto neby ́vajı ́ navrz ̌ene ́ pro simulace jemne ́ho rozlis ̌enı ́ coby vy 'stupy regiona ́lnı ́ch klimaticky ́ch modelu ̊. V te ́to pra ́ci je navrz ̌ena nova ́ metoda statisticke ́ho processingu, ktera ́ je na 'sledne ̌ aplikova ́na na projkce koncentracı ́ ozonu vytvor ̌ene ́ modely WRF-Chem a CAMx ve dvou budoucı ́ch obdobı ́ch za sce ́na ́r ̌u ̊ RCP4.5 a RCP8.5. Vy 'sledky ukazujı ́ komplexnı ́ prostorove ̌ prome ̌nne ́ sezo ́nnı ́ prome ̌ny v obdobı ́ 2026-2035 za obou sce ́na ́r ̌u ̊, ale v obdobı ́ 2045-2055 ukazujı ́ celkove ́ snı ́z ̌enı ́ koncentracı ́ za RCP4.5 a zvy 's ̌enı ́ za RCP8.5. 1

Many factors and processes are expected to be altered in the troposphere under the on- going climate change. This is likely to affect the regime of concentrations of tropospheric species. In the case of ozone, the situation is somehow uncertain, because the expected changes are often contradictory for its production and destruction. To project its future concentrations, chemistry climate models are used, but they usually exert systematical er- rors which can originate from many different sources. Although there are statistical tools which are used to compensate these schortcomings, they are often not designed for the fine resolution simulations at the output of regional climate models. In this study, a new method of statistical processing is proposed and applied upon projections of ozone concentrations projected with WRF-Chem and CAMx models in two future periods under the RCP4.5 and RCP8.5 scenarios. The results show complex spatially variable seasonal changes in 2026- 2035 under both scenarios, but in 2045-2055 an overall decrease in concentrations under RCP4.5 and an increase under RCP8.5. 1