English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

In situ observation of the atmospheric CO2, CH4, and CO mixingratios at Hateruma Island (HAT, 24.05° N, 123.80° E) oftenshow synoptic-scale variations with correlative elevations during winter,associated with air transport from the East Asian countries. We examinewinter (November– March) trends in ΔCH4 / ΔCO2,ΔCO / ΔCO2, and ΔCO / ΔCH4observed at Hateruma over the period 1999 to 2010. To investigate therelationship between the East Asian emissions and the short-term variationsin the atmospheric mixing ratios, we use the FLEXPART Lagrangian particledispersion model (LPDM). The observed ratios ΔCH4 / ΔCO2 and ΔCO / ΔCO2 both show an overall gradualdecrease over the study period due to a recent rapid increase in fossil fuelconsumption in China. We note, however, that the decreasing rates of ΔCH4 / ΔCO2 and ΔCO / ΔCO2 showgradual decrease and increase, respectively, during the entire observationperiods used in this study. The ΔCO / ΔCH4 slope, on the other hand, showsan increasing trend during 1999–2004 but a decrease during 2005–2010.Calculation of the concentration footprint for the atmospheric observation atHAT by using the FLEXPART LPDM indicates that most of the short-termvariations are caused by emission variations from northern and eastern China.Combined with a set of reported emission maps, we have estimated the temporalchanges in the annual CH4 and CO emissions from China under theassumption that the estimate of the fossil-fuel-derived CO2 emissionsbased on the energy statistics are accurate. The estimated annual CH4emissions, corresponding to nonseasonal sources or anthropogenic sourceswithout rice fields, show a nearly constant value of39 ± 7 TgCH4 yr−1 during 1998–2002, and then graduallyincrease to 46 ± 8 TgCH4 yr−1 in 2009/2010. The estimatedannual CO emissions increase from 134 ± 32 TgCO yr−1 in1998/1999 to 182 ± 42 TgCO yr−1 in 2004/2005, level off after2005, and then slightly decrease to less than 160 TgCO yr−1 in2008–2010

atmospheric chemistry and physics

Temporal changes in the emissions of CH&amp;lt;sub&amp;gt;4&amp;lt;/sub&amp;gt; and CO from China estimated from CH&amp;lt;sub&amp;gt;4&amp;lt;/sub&amp;gt; / CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; and CO / CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; correlations observed at Hateruma Island