Defense Meteorological Satellite Program Research Articles

The Quasipersistent Feature of Highly Structured Field‐Aligned Currents in the Duskside Auroral Oval: Conjugate Observation Via Swarm Satellites and a Ground All‐Sky Imager

AbstractDuring northward interplanetary magnetic field (IMF), irregular magnetic perturbations were observed in the duskside aurora oval via Swarm satellites instead of large‐scale Region 1/2 magnetic perturbations. By taking advantage of Swarm constellation measurements, and their conjugate observations with an all‐sky imager on the ground, the features of the irregular magnetic perturbations were examined. Detailed analysis of the data from Swarm A and Swarm C for two events demonstrated that the irregular magnetic perturbations are a result of highly structured quasistatic field‐aligned currents (FACs), not dynamic Alfvén waves. The typical latitudinal size of the upward FACs is 20–30 km. In each region of the upward FACs, 630‐nm aurora emissions are relatively strong, indicating that the energy flux of precipitating electrons having energies of a few hundred electron volts is high in each of the upward FAC regions. The enhanced mesoscale auroras continued to exist for at least approximately 30 min. These indicate that the mesoscale FAC structures also have quasipersistent features. The precipitating particle data from the Defense Meteorological Satellite Program satellite, which passed through the field of view of the all‐sky imager, indicate that the source of the precipitating particles is the duskside low‐latitude boundary layer (LLBL). We suggest that the highly structured quasipersistent FACs flow along the magnetic field lines connected to the duskside LLBL where cold dense ions exist. The highly structured FACs in the duskside aurora oval are the phenomena that are pertinent to the magnetosphere for a northward IMF condition, not a simple remnant of the typical Region 1.

Airport’s Throughput Estimation Using Nighttime Light Data in China Mainland

Accurate information about the airport's throughput is crucial for monitoring traffic flow, evaluating the development status of aviation industry. In this letter, we used the Suomi National Polar-orbiting Partnership-Visible Infrared Imaging Radiometer (NPP-VIIRS) and the Defense Meteorological Satellite Program's Operational Linescan System (DMSP-OLS) nighttime light (NTL) data as effective proxies for evaluating and monitoring the airport's throughput power in China mainland. The results show that there is a significant positive correlation between the NTL intensity and the airport's throughput ( R <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> > 0.85). The NPP-VIIRS NTL data have been proved to not only distinguish the airport area and nonairport area but also build airport's NTL feature space. This letter reveals that the NTL images provide powerful remote sensing data sources to model the spatiotemporal dynamics of airport's throughput of China mainland at a large spatial scale.

A harmonized global nighttime light dataset 1992\u20132018

Nighttime light (NTL) data from the Defense Meteorological Satellite Program (DMSP)/Operational Linescan System (OLS) and the Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi National Polar-orbiting Partnership satellite provide a great opportunity for monitoring human activities from regional to global scales. Despite the valuable records of nightscape from DMSP (1992–2013) and VIIRS (2012–2018), the potential of the historical archive of NTL observations has not been fully explored because of the severe inconsistency between DMSP and VIIRS. In this study, we generated an integrated and consistent NTL dataset at the global scale by harmonizing the inter-calibrated NTL observations from the DMSP data and the simulated DMSP-like NTL observations from the VIIRS data. The generated global DMSP NTL time-series data (1992–2018) show consistent temporal trends. This temporally extended DMSP NTL dataset provides valuable support for various studies related to human activities such as electricity consumption and urban extent dynamics.

A Generic Global-to-Local Quantitative Transformation Model (GGTLQTM) for Modeling Socioeconomic Indicators From DMSP-OLS Nighttime Light Imagery

To expand the application range of Defense Meteorological Satellite Program Operational Line Scanner (DMSP-OLS) nighttime light (NTL) imagery and fully utilize the value of such imagery in this letter of socioeconomic indicators on a small scale, this letter proposes a novel model, that is, the generic global-to-local quantitative transformation model (GGTLQTM), and a new comprehensive indicator of accuracy, that is, adjusted normalized cross-validation (ANCV). The consistency of the GGTLQTM, from its fundamental hypotheses to conclusions, was studied to discuss the reliability of the model. Thirteen county-level administrative regions of Wuhan, China, were selected as the research areas. It was found that the GGTLQTM can 1) obtain a relatively high accuracy by selecting an optimal linear or nonlinear model, that the quadratic polynomial is the optimal GGTLQTM assessed by ANCV; 2) be established without relying on strict hypotheses; and 3) detect universal (global) homogeneity and individual (local) heterogeneity. In letter, the proposed GGTLQTM not only expands the application range of DMSP-OLS NTL remote sensing but also proposes a new idea on the geoscience-scale transformation, which helps integrate geoscience and remote sensing.

Monitoring Regional Urban Dynamics Using DMSP/OLS Nighttime Light Data in Zhejiang Province

Accurate monitoring of urban regions and urban sprawls is critical to the detection and assessment of regional development. The nighttime light images of Defense Meteorological Satellite Program’s Operational Linescan System (DMSP/OLS) provide us direct solutions to make spatial descriptions of urban regions. Unfortunately, accurate monitoring of urban regions is apt to be hampered due to the shortages of the DMSP/OLS data. In this study, we utilized a new urban region extraction strategy based on the edge-detection method which is widely applied in automatic digital image processing. The edges of urban areas in Zhejiang province were identified based on the distributions and values of pixels. Compared with other traditional methods, the urban regions extracted in this study present a higher overall accuracy and kappa coefficient (OA = 93.1409%; Kappa = 0.8755). Two periods of the urban dynamic process and urban sprawl pattern in Zhejiang from 1992–2013 were further detected by the proposed method. At city level, the drastic increase in urban areas was found in cities of Hangzhou and Ningbo. This study provides an objective and convenient solution to the accurate identification of urban regions, which is also an important step to better understand the urban dynamics and urban development.

Monitoring long-term shoreline dynamics and human activities in the Hangzhou Bay, China, combining daytime and nighttime EO data

ABSTRACT Shorelines are vulnerable to anthropogenic activities including urbanization, land reclamation and sediment loading. Shoreline changes may be a reflection of the degradation of coastal ecosystems because of human activities. Understanding the shoreline dynamics is, therefore, a topic of global concern. Earth observation data, such as multi-temporal satellite images, are an important resource for assessing changes in coastal ecosystems. In this research, we used Google Earth Engine (GEE) to monitor and map historical shoreline dynamics in the Hangzhou Bay in China where the Qiantang River flows into the East China Sea. Specifically, we aimed to capture and quantify both the spatial and temporal shoreline changes and to assess the link between anthropogenic activities and shoreline changes on the integrity of this coastal area. We implemented a Tasselled Cap analysis (TCA) on Landsat imagery from 1985 to 2018 in GEE to calculate the wetness coefficient. We then applied Otsu method for automatic image thresholding on the wetness coefficient to detect waterbodies and shoreline changes. Further, we adopted the nighttime light data from the Defense Meteorological Satellite Program’s Operational Linescan System (DMSP-OLS) from 1992 to 2013 as a proxy of human activities. The results show that in the hotspot areas, the shoreline has moved by more than 5 km in the last decades, accounting for approximately 900 km2 of land accretion. Within this area, the human activity, indicated by the intensity of nighttime light, increased significantly. The results of this work reveal the influence of human activities on the shoreline dynamics and can support policies that promote the sustainable use and conservation of coastal environments. Our methodology can be transferred and applied to other coastal zones in various regions and scaled up to larger areas.

A novel cross-sensor calibration method to generate a consistent night-time lights time series dataset

ABSTRACT Night-time lights (NTLs) collected from the Defense Meteorological Satellite Program‘s Operational Linescan System (DMSP-OLS) and the Visible Infrared Imaging Radiometer Suite (VIIRS) of the Suomi National Polar Partnership satellite have been widely used in multiple disciplines. However, the defects of DMSP and VIIRS data itself, and the inconsistency between them, hinder their applications in long-term finer studies. Despite some effective efforts, existing relevant researches are still limited by the shortcomings of data inaccessibility, data deficiency neglection, and spatial resolution degradation. To resolve these issues, a novel cross-sensor calibration method was developed in this article by considering three Chinese metropolises (Beijing, Shanghai, and Guangzhou) as the study area. First, the original DMSP NTL images for 2000–2013 were calibrated through stepwise calibration, background noise removal and vegetation adjustment. Second, stable VIIRS annual composites for 2012–2019 were produced after seasonal noise removal, yearly aggregation, background noise removal, vegetation adjustment, and outliers correction. Third, a power regression model was applied to align pixel values of the processed DMSP and the processed VIIRS data for the overlapped years, and consistent NTLs for 2000–2019 were further generated using the regression results. The evaluations based on statistical coefficients, spatial patterns, profile curves, dynamic changes, and correlations with socioeconomic statistics, indicated the robustness and effectiveness of the proposed approach in filling the gaps between DMSP and VIIRS data. The consistent, continuous, and stable NTL time series could serve as input data for further applications, such as urban dynamics capture, economic growth estimation, and population distribution mapping.

Shift Estimation for DMSP-OLS Night-Time Light Rasters in 2009–2011

Night-time lights in satellite imagery are considered to be related to population and human activities such as urbanization, energy consumption, and CO2 emissions. The Defense Meteorological Satellite Program (DMSP) Operational Line-Scan System (OLS) instrument has provided a long-term dataset of global night lights covering more than two decades. However, the F162009, F182010, and F182011 rasters of DMSP-OLS version 4 night-time lights time series are shifted for unknown reasons, which may influence spatial time series comparisons. This study presents a statistical correlation method based on fast Fourier transform (FFT) to estimate these shifts in longitude and latitude with greater accuracy, and recommends the use of them to generate the accompanying Tiff World (TFW) files of tiff images for these rasters.

Modeling and spatio-temporal analysis of city-level carbon emissions based on nighttime light satellite imagery

Climate warming due to carbon emissions has been recognized as a threat to food security, human health and natural ecosystem, and carbon emission reduction is a challenging job for each country in the world. In this study, an ensemble structure-based neural network model (NNEnsemble) is proposed to analyze the nonlinear relationship between the Defense Meteorological Satellite Program Operational Line-Scan System (DMSP-OLS) nighttime stable light (NSL) data, and province-scale statistical data on carbon emissions. Given the challenge of obtaining urban-scale carbon emission data, a weighted coefficient strategy by using the NSL data were employed to analyze the carbon emissions at the urban scale. The performance of the proposed method was found to be superior to that of comparable methods with respect to various evaluation indices. Under these circumstances, a hot spot and Standard deviational ellipse analysis of three northeast provinces in China was conducted from 1998 to 2013. The results can promote a better understanding of the spatio-temporal characteristics of carbon emissions in three northeastern Chinese provinces. Moreover, the developed application software based on NNEnsemble can serve as a basis for the development of carbon emission mitigation policies for other provinces.

Throat aurora observed by DMSP/SSUSI in a global view

Throat aurora was defined based on the ground observations near local noon and has been suggested to be the ground signature of an indentation on the subsolar magnetopause. A global view of the auroral oval with throat aurora will be critical for inferring global processes at the magnetopause, but it has never been achieved. Using imaging spectrograph observations from Defense Meteorological Satellite Program satellites, for the first time, here we show typical throat auroras in a global view and reveal some important observational facts as follows. (1) The throat auroras can be as long as ~8 degrees in latitudinal direction, which is hardly to be fully seen in the ground-based camera. (2) The plasma flows and field aligned currents associated with throat aurora show consistences with previous radar observations, which have been suggested to be the observational evidence of magnetopause reconnection. (3) Most importantly, we confirmed that the electron and ion precipitations associated with throat aurora are always spatially separated, i.e., electrons in the east and ions in the west. The observational results not only establish a new picture of the aurora oval near local noon, but also provide important support to a conceptual model of throat aurora.

Spatiotemporal Variations in Energy Consumption and Their Influencing Factors in China Based on the Integration of the DMSP-OLS and NPP-VIIRS Nighttime Light Datasets

With the speedy growth of economic development, the imbalance of energy supply and demand pose a critical challenge for the energy security of our country. Meanwhile, the increasing and excessive energy consumption lead to the greenhouse effect and atmospheric pollution, greatly threatening the survival and development of human beings. This study integrated two nighttime light remote sensing datasets, namely Defense Meteorological Satellite Program’s Operational Linescan System (DMSP-OLS) data and Suomi National Polar-orbiting Partnership (NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) data, to extend the temporal coverage of the study. Then, the distributions of China’s energy consumption from 1995 to 2016 at a 1-km resolution were estimated using different models and the spatiotemporal variations of energy consumption were explored on the basis of the best estimated results. Next, the factors influencing China’s energy intensity on the provincial level were investigated based on the spatial econometric model. The results show that: (1) The integrated nighttime light datasets can be successfully applied to estimate the dynamic changes of energy consumption. Moreover, the panel data model established in our research performed better than the quadratic polynomial model. (2) During the observation period, the energy consumption in China significantly increased, especially in the Yangtze River Delta, the Pearl River Delta, the Beijing–Tianjin–Hebei region, eastern coastal cities, and provincial capitals. (3) Different from the random spatial distribution pattern of energy consumption on the provincial level, the spatial distribution of energy consumption on the prefectural level has significant clusters, and its spatial agglomeration was strengthened year by year during the research period. (4) The spatial Durbin model (SDM) with a spatial fixed effect has been proved to be more suitable to explore the impact mechanism of China’s energy consumption. Among the four socio-economic factors, industrial structure has the greatest impact on the provincial energy intensity in China. Moreover, the changes in industrial structure and foreign direct investment (FDI) can not only influence the local energy intensity but also affect the energy intensity of the neighboring provinces.

A Fundamental Climate Data Record of SMMR, SSM/I, and SSMIS brightness temperatures

Abstract. The Fundamental Climate Data Record (FCDR) of Microwave Imager Radiances from the Satellite Application Facility on Climate Monitoring (CM SAF) comprises inter-calibrated and homogenized brightness temperatures from the Scanning Multichannel Microwave Radiometer (SMMR), the Special Sensor Microwave/Imager (SSM/I), and the Special Sensor Microwave Imager/Sounder SSMIS radiometers. It covers the time period from October 1978 to December 2015 including all available data from the SMMR radiometer aboard Nimbus-7 and all SSM/I and SSMIS radiometers aboard the Defense Meteorological Satellite Program (DMSP) platforms. SMMR, SSM/I, and SSMIS data are used for a variety of applications, such as analyses of the hydrological cycle, remote sensing of sea ice, or as input into reanalysis projects. The improved homogenization and inter-calibration procedure ensures the long-term stability of the FCDR for climate-related applications. All available raw data records from different sources have been reprocessed to a common standard, starting with the calibration of the raw Earth counts, to ensure a completely homogenized data record. The data processing accounts for several known issues with the instruments and corrects calibration anomalies due to along-scan inhomogeneity, moonlight intrusions, sunlight intrusions, and emissive reflector. Corrections for SMMR are limited because the SMMR raw data records were not available. Furthermore, the inter-calibration model incorporates a scene dependent inter-satellite bias correction and a non-linearity correction in the instrument calibration. The data files contain all available original sensor data (SMMR: Pathfinder level 1b) and metadata to provide a completely traceable climate data record. Inter-calibration and Earth incidence angle normalization offsets are available as additional layers within the data files in order to keep this information transparent to the users. The data record is complemented with noise-equivalent temperatures (NeΔT), quality flags, surface types, and Earth incidence angles. The FCDR together with its full documentation, including evaluation results, is freely available at: https://doi.org/10.5676/EUM_SAF_CM/FCDR_MWI/V003 (Fennig et al., 2017).

Constructing a New Inter-Calibration Method for DMSP-OLS and NPP-VIIRS Nighttime Light

The anthropogenic nighttime light (NTL) data that are acquired by satellites can characterize the intensity of human activities on the ground. It has been widely used in urban development assessment, socioeconomic estimate, and other applications. However, currently, the two main sensors, Defense Meteorological Satellite Program’s Operational Linescan System (DMSP-OLS) and Suomi National Polar-orbiting Partnership Satellite’s Visible Infrared Imaging Radiometer Suite (NPP-VIIRS), provide inconsistent data. Hence, the application of NTL for long-term analysis is hampered. This study constructed a new inter-calibration method for DMSP-OLS and NPP-VIIRS nighttime light to solve this problem. First, NTL data were processed to obtain vicarious site across China. By comparing different candidate models, it is discovered the Biphasic Dose Response (BiDoseResp) model, which is a weighted combination of sigmoid functions, can best perform the regression between DMSP-OLS and logarithmically transformed NPP-VIIRS. The coefficient of determination of BiDoseResp model reaches 0.967. It’s residual sum of squares is 6.136 × 10 5 , which is less than 6.199 × 10 5 of Logistic function. After obtaining the BiDoseResp-calibrated VIIRS (BDRVIIRS), we smoothed it by a filter with optimal parameters to maximize the consistency. The result shows that the consistency of NTL data is greatly enhanced after calibration. In 2013, the correlation coefficient between DMSP-OLS and original NPP-VIIRS data in the China region is only 0.621, while that reaches to 0.949 after calibration. Finally, a consistent NTL dataset of China from 1992 to 2018 was produced. When compared with the existing methods, our method is applicable to the full dynamic range of DMSP-OLS. Besides, it is more suitable for country or larger scale areas. It is expected that this method can greatly facilitate the development of research that is based on the historical NTL archive.

Auroral Omega Bands are a Significant Cause of Large Geomagnetically Induced Currents

AbstractThe strongest event of geomagnetically induced currents (GIC) detected by the North‐West Russian GIC network occurred during the main phase of the magnetic storm on 28 and 29 June 2013. Extremely high value, 120 A, was recorded in the 330 kV transformers on Kola Peninsula in the 04–07 magnetic local time (MLT) sector. The Defense Meteorological Satellite Program (DMSP) spacecraft took a sequence of ultraviolet (UV) auroral images in the southern hemisphere and observed multiple omega bands. The ionospheric equivalent electric currents based on the International Monitor for Auroral Geomagnetic Effects (IMAGE) magnetometer network reveal a sequence of current vortex pairs moving eastward with the speed of 0.5–2.5 km/s that fits to the electrodynamics scheme of omega bands. Although the temporal variations of the associated current system are slow, the omega bands can be responsible for strong magnetic variations and GIC due to fast propagations of currents in the azimuthal direction.

Statistical Study of Ion Upflow Associated with Subauroral Polarization Streams (SAPS) at Substorm Time

AbstractWe present a statistical study of the ion upflow associated with subauroral polarization streams (SAPS) in the ionospheric subauroral region at different substorm times using three Defense Meteorological Satellite Program satellite (F16–F18) data for five years (2010–2014) in the Northern Hemisphere. The results show similarities between SAPS and the ion upflow at different intensity of substorms both in occurrence rate distribution and velocity distribution. In comparison to SAPS, the distribution of the ion upflow shows the smaller occurrence region and lower velocity. We also find that frictional heating plays an important role in ion upflow from the SAPS region. The intense substorms can trigger strong SAPS channels, enhanced frictional heating, and large ion upflow. In addition, there is a moderate linear correlation between SAPS velocity and field‐aligned velocity that is consistent with some previous findings. Our results also show that frictional heating can gradually dominate the ion upflow process in intense substorms, while it may not be the only factor to affect the whole upflow process.

Spatial variation of climate change issues using remote sensing technique

The assessment of climate change can be carried out by analysing rainfall variability, temporal climatic changes, spatial interpolation of climatic factors and climatic risking. The climatic changes have consequences on precipitation pattern changes, temperature variation, and crop growing season alteration, increase of sea ice and grounded ice sheets. This has implications on ecosystem, human health, settlement and agriculture. Some of the repercussions attributed to temperature and precipitation increase is an increase of Cyclonic activities with increase of cyclonic wind speeds, Increase in Extreme Precipitation events like floods and droughts, agricultural yield is projected to decrease and negative impact on subsistence agriculture. The Tropical Cyclones intensifying in eastern Indian Ocean and crossing the coasts of Indian subcontinent year after year is a major cause of concern. The Latent Heat Release (LHR) of cyclones of Bay of Bengal carried out using advanced sensors like SSM/I (Special Sensor Microwave/Imager) on-board DMSP satellites (Defence Meteorological Satellite Program of US) for assessing spatial distribution of precipitation since LHR is responsible for maintenance and intensification of tropical cyclones and LHR can also enable measurement of brightness temperatures of atmospheric/ocean surfaces. The images of the clouds in visible and infrared region provide information about cloud aerial extent, type, and growth/decay. The raining clouds have high visible band reflectance and are tall due to upward motion indicating deep convection. These issues pertaining to climate changes through Remote sensing techniques is discussed in the paper.

FDTD Modeling of High‐Frequency Waves Through Ionospheric Plasma Irregularities

AbstractElectromagnetic wave scattering and scintillation can occur at high latitudes of the Earth when polar cap patches are present. Polar cap patches range in size from 100 to 1,000 km and have densities on the order of 2–10 times that of the background ionosphere. Within polar cap patches, plasma irregularities caused by gradient drift instabilities are observed throughout the patch as elongated slivers. These irregularities vary in size from centimeters to tens of kilometers. Three major challenges must be overcome to thoroughly study high‐frequency electromagnetic wave interactions with polar cap patches: (1) the complex geometrical features of the irregularities within the patches must be accommodated; (2) the non‐approximated Maxwell's equations should be solved to account for all the physics of electromagnetic wave propagation, scattering, diffraction, etc.; and (3) the physics of electromagnetic wave interactions with magnetized ionospheric plasma must be included. In this paper, the finite‐difference time‐domain (FDTD) method is used to overcome the above three challenges and solve for electromagnetic wave interactions with plasma irregularities within a polar cap patch. Irregularities and patch profiles are generated using Defense Meteorological Satellite Program data and incorporated into the FDTD model. The transmission coefficients for high‐frequency electromagnetic wave propagation through perturbed and unperturbed ionospheres, as well as for magnetized and unmagnetized ionospheric plasma ionospheres are calculated. From these simulations, the effects of small‐scale irregularities on high‐frequency propagation are observed.

Fine‐Scale Visualization of Aurora in a Wide Area Using Color Digital Camera Images From the International Space Station

AbstractThe full‐color photographs of aurora have been taken with digital single‐lens reflex cameras mounted on the International Space Station (ISS). Since these photographs do not have accurate time and geographical information, in order to use them as scientific data, it is necessary to calibrate the imaging parameters (such as looking direction and angle of view of the camera) of the photographs. For this purpose, we calibrated the imaging parameters using a city light image taken from the Defense Meteorological Satellite Program satellite following the method of Hozumi et al. (2016, https://doi.org/10.1186/s40623-016-0532-z). We mapped the photographs onto the geographic coordinate system using the calibrated imaging parameters. To evaluate the accuracy of the mapping, we compared the aurora taken simultaneously from ISS and ground. Comparing the spatial structure of discrete aurora and the temporal variation of pulsating aurora, the accuracy of the data set is less than 0.3 s in time and less than 5 km in space in the direction perpendicular to the looking direction of the camera. The generated data set has a wide field of view ( 1,100 900 km), and their temporal resolution is less than 1 s. Not only that, the field of view can sweep a wide area ( 3,000 km in longitude) in a short time ( 10 min). Thus, this new imaging capability will enable us to capture the evolution of fine‐scale spatial structure of aurora in a wide area.

Multi‐instrumental Observations of the Quasi‐16‐Day Variations From the Lower Thermosphere to the Topside Ionosphere in the Low‐Latitude Eastern Asian Sector During the 2017 Sudden Stratospheric Warming Event

AbstractVariations of the low‐latitude ionosphere in the eastern Asian sector during the 2017 sudden stratospheric warming (SSW) were studied with multi‐instrumental observations that correspond to different altitudes. Specifically, the variations of the topside ionosphere as high as over 830 km were investigated with data from the Swarm B satellite (~500 km), the Defense Meteorological Satellite Program F15 satellite (~830 km), and the Meteorological Operational satellite‐A (~830 km). The main results are as follows. (1) Simultaneous variations were detected in the ionospheric parameters from the E region to the topside ionosphere around the first peak warming of the 2017 SSW. (2) These variations exhibited similar quasi‐16‐day (Q16D; ~14.5‐day) periods, and these periods were most significant just before the first peak warming. (3) These simultaneous Q16D variations were not due to the solar extreme ultraviolet irradiance or geomagnetic activities but were probably driven from below, by planetary waves or semidiurnal lunar tides that enhanced during the SSW. (4) The Q16D variation of the topside ionospheric electron density at ~830 km was probably driven not only by the upward mapping electric field modulated in the E region dynamo but also by the electric field modulated in the F region dynamo.

Shining a new light on the environmental Kuznets curve for CO2 emissions

Abstract This paper examines the existence of an inverted U-shaped relationship between income and CO2 emissions from fossil fuels for a panel of 161 countries over the period 1992–2012. Our contribution, empirical in nature, is threefold. (i) We estimate the Environmental Kuznets Curve for CO2 emissions using three conventional measures of GDP taken from the PWT and the WDI and show that the results of the estimates are unstable and that the turning points are dependent on the measure of GDP. (ii) We use a new dataset of GDP based on the Defense Meteorological Satellite Program's Operational Linescan System (DMSP-OLS) nighttime light imagery as a proxy for the development level, and using these data, which are less prone to the measurement errors in the System of National Accounts statistics, we find evidence for the existence of an Environmental Kuznets Curve for CO2 emissions. (iii) We apply a U test that confirms that the estimated extreme point is within our data range. The evaluated turning point, beyond which CO2 emissions start to fall as income rises, is considerably lower than earlier studies show, and thus, our results provide more optimistic prospects of the possible environmental benefits of economic growth.