Measurements from the Ozone Monitoring Instrument are used to investigate the temporal and spatial dynamics of global nitrogen dioxide (NO 2 ). The results show that the global tropospheric column NO 2 increased by 11.10% during 2005 to 2010 at a 1.76% annual growth rate. The largest tropospheric and total NO 2 columns are mainly concentrated in the industrialized regions of North America, Europe, and east Asia. The large values of column NO 2 are also observed and scattered in South America, Africa, and Indonesia due to biomass burning and savannah fires. Average tropospheric column NO 2 increased by 32.62% at a 4.82% annual rate over eastern Asia. On the contrary, the trend decreased by 35.47% at a 7.04% annual rate over eastern America. The trend was not significant over Europe as a whole, where a decrease was observed over western and southern Europe and an increase was observed over eastern and northern Europe. Over the polluted urban areas, the ratios of tropospheric to total column NO 2 are larger than 0.6 and the correlation coefficients are larger than 0.8. This can be mainly attributed to the anthropogenic NO x emissions over land, and it is noteworthy that the ratios are higher than 0.8 (correlation coefficients >0.95 ) over northern China.
Methane (CH4), a significant atmospheric trace-gas, controls numerous chemical processes and species in the
troposphere and stratosphere and is also a strong greenhouse gas with significantly adverse environmental impacts. Since
the SCIAMACHY on the Envisat was in orbit since 2002, CH4 measurements at a regional scale became available. This
study (1) firstly improved the spatial resolution of 0.5°×0.5° lat/lon grid data provided by University of Bremen IUP/IFE
SCIAMACHY near-infrared nadir measurements using the scientific retrieval algorithm WFM-DOAS to 0.1°×0.1°
lat/lon with the ordinary Kriging method, (2) then analyzed the spatial-temporal characteristics of atmospheric CH4
concentration in the Yangtze River basin (YRB), China from 2003 to 2005, (3) finally analyzed the relations with the
main environmental factors: the precipitation from GSMaP MVK+ 0.1x 0.1 lat/lon degree grid data and the temperature
from 147 meteorological stations in the YRB. The analysis shows that atmospheric methane concentration has significant
and obvious characteristics of the spatial distribution of the inter-annual cycle fluctuations and seasonal characteristics
during the year, and points out that the temperature is the main impact factor.
Land structure and amount directly influence urban development, since it is an elementary resource for various activities
in urban systems. However, land use zoning in urban system is often conducted from the view of economic and social
benefits, not considering ecological benefit. Taking Nanjing city as the study area, the present paper studied land cover
constitution of different land use zoning and constructed the quantitative relationship between urban ecological
parameters of land surface temperature (LST) and land surface dryness (LSD) and land cover constitution. Land cover
information was acquired from IKONOS data based on a decision tree method, LST was retrieved from the thermal band
of Landsat ETM+ data using mono-window algorithm, and LSD was calculated from the LST/NDVI space. Analysis
results showed that land cover constitutions within different land use zonings have great variations, and the relationships
between ecological parameters and land cover constitution also showed a close correlation; the percent vegetated area
had strong negative relationship with LST and LSD, while the percent impervious surface showed obvious positive
relationship with LST and LSD. These conclusions should be considered in urban ecological environment management.
Methane (CH4) is regarded as one of the most important greenhouse gases due to its radiative forcing. Since the
SCIAMACHY instrument on ENVISAT was in orbit, CH4 measurements at a regional scale became available. However,
the spatial resolution of 0.5 deg latitude × 0.5 deg longitude omits many detailed spatial variations. The present study
aimed to improve the spatial resolution of the retrieved atmospheric CH4 concentrations with the aid of the normalized
difference vegetation index (NDVI) and land surface temperatures (LST) from MODIS with the spatial resolution of 0.05
deg latitude × 0.05 deg longitude. The gridded CH4 concentrations were firstly converted into point files, which were
then divided into training and testing groups. Three methods of Ordinary Kriging, Regression Kriging, and Co-Kriging
were used to simulate the spatial distribution of CH4 concentrations. The accuracy assessment showed that the
Co-Kriging method combing with NDVI obtained the lowest mean predication error and root mean square prediction
error. Thus, the spatially distributed atmospheric CH4 with the resolution of 0.05 deg latitude ×0.05 deg longitude was
acquired.
Landsat TM/ETM+ data have been proved a useful tool to measure urban heat island (UHI) effect. In this paper, five methods - DN value or at-sensor brightness temperature, land surface temperature (LST) retrieved by spectral emissivity correction, mono-window algorithm, generalized single-channel method with and without near-surface temperature, to denote the spatial distribution of the UHI effect from the thermal band of ETM+ data are compared. The land surface emissivity (LSE) values required to retrieve LST was estimated from the NDVI Thresholds Methods, combing with the other six bands provided by the ETM+ data. Finally, we presented a comparison between the five temperatures retrieved by the five algorithms over Nanjing City. The results showed that the three methods of mono-window algorithm and the generalized single-channel method with or without near-surface temperature obtained the similar UHI effect results; DN value also owned high correlation coefficient with LSTs by the three mono-channel methods, so it could be used to denote the spatial variation of UHI effect in some degree; and the value of spectral emissivity corrected LST was much different with that from other four methods.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.