An international effort to improve ozonesonde data quality and to reevaluate historical records has made significant improvements in the accuracy of global network data. However, between 2014 and ...2016, ozonesonde total column ozone (TCO; O3) at 14 of 37 regularly reporting stations exhibited a sudden dropoff relative to satellite measurements. The ozonesonde TCO drop is 3–7% compared to satellite and ground‐based TCO, and 5–10% or more compared to satellite stratospheric O3 profiles, compromising the use of recent data for trends, although they remain reliable for other uses. Hardware changes in the ozonesonde instrument are likely a major factor in the O3 dropoff, but no single property of the ozonesonde explains the findings. The bias remains in recent data. Research to understand the dropoff is in progress; this letter is intended as a caution to users of the data. Our findings underscore the importance of regular ozonesonde data evaluation.
Plain Language Summary
Balloon‐borne ozonesondes provide accurate measurements of atmospheric ozone (O3) from the surface to above 30 km with high vertical resolution. Dozens of global stations have regularly launched ozonesondes for decades, and they provide vital information for improving O3‐measuring satellite algorithms, tracking recovery of the stratospheric O3 layer, and our understanding of surface to lower stratospheric O3 changes in an evolving climate. We present the discovery of an apparent instrument artifact that has caused total column O3 measurements from about a third of global stations to drop by 3–7% starting in 2014–2016, limiting their suitability for calculating O3 trends. Work is underway to solve the problem, but the exact cause of the drop is still unknown. This letter serves as a caution to the community of ozonesonde data users.
Key Points
We report a drop in ozonesonde total column O3 of 3–7% relative to independent measurements at a third of sites beginning around 2014
Comparisons with satellite stratospheric O3 profiles show the artifact loss peaking at 5–10% or more in the middle and upper stratosphere
Changes in the ozonesonde instrument are apparently associated with the dropoff, but no single factor appears to be the cause
Since the late 1990s, remotely sensed night-time lights (NTL) satellite imagery has been shown to correlate with socioeconomic parameters including urbanization, economic activity, and population. ...More recent research demonstrates that multitemporal NTL data can serve as a reliable proxy for change over time in these variables whether they are increasing or decreasing. Time series analysis of NTL data is especially valuable for detecting, estimating, and monitoring socioeconomic dynamics in countries and subnational regions where reliable official statistics may be lacking. Until 2012, multitemporal NTL imagery came primarily from the Defense Meteorological Satellite Program - Operational Linescan System (DMSP-OLS), for which digital imagery is available from 1992 to 2013. In October 2011, the launch of NASA/NOAA's Suomi National Polar-orbiting Partnership satellite, whose Visible Infrared Imaging Radiometer Suite (VIIRS) sensor has a Day/Night Band (DNB) specifically designed for capturing radiance from the Earth at night, marked the start of a new era in NTL data collection and applications. In light of these advances, this paper reviews progress in using multitemporal DMSP-OLS and VIIRS imagery to analyze urbanization, economic, and population dynamics across a range of geographic scales. An overview of data corrections and processing for comparison of multitemporal NTL imagery is provided, followed by a meta-analysis and integrative synthesis of these studies. Figures are included that visualize the capabilities of DMSP-OLS and VIIRS to capture socioeconomic change in the post-Soviet Russian Far East and war-torn Syria, respectively. Finally, future directions for NTL research are suggested, particularly in the areas of determining the fundamental causes of observed light and in leveraging VIIRS' superior sensitivity and spatial and radiometric resolution.
•This is a review of research to date using multitemporal night-time lights data.•Studies using NTL data from DMSP-OLS and Suomi NPP VIIRS DNB are compared.•Multitemporal NTL data can serve as a reliable proxy for socioeconomic dynamics.•NTL better predict GDP than population & long-term growth than short-term decline.•Future research can leverage VIIRS' superior sensitivity and on-board calibration.
Tässä artikkelissa tarkastelen, mitä soittimia käytettiin ja miten kirkkolaulun kehittämisessä 1800-luvun Suomessa, sekä millaista keskustelua aiheesta käytiin, kiinnittäen huomion erityisesti ...kansanomaisen estetiikan ja taide-estetiikan välisiin eroihin. Tutkimusaineistona ovat vuosisadan aikana painetut koraalikirjat, messusävelmistöt ja kirkolliseen käyttöön tarkoitetut musiikkioppaat, käsinkirjoitetut koraalikirjat, kirkkolaulun tilaa käsitelleet sanomalehtikirjoitukset sekä aiempi aihetta sivuava kirjallisuus. Koska aiheesta ei ole olemassa kattavia lähteitä, olen mikrohistorian tutkimusmenetelmiä hyödyntäen koonnut yhteen sieltä täältä löytyviä tiedonmurusia ja muodostanut niiden avulla kokonaiskuvaa, joka kuitenkin jää väkisinkin osittain vajaaksi aineiston sirpaleisuuden vuoksi.
The Visible Infrared Imaging Radiometer Suite (VIIRS) sensor aboard the Suomi National Polar‐orbiting Partnership spacecraft has successfully operated since its launch in October 2011. The VIIRS ...collects data in 22 spectral bands that are calibrated by a set of onboard calibrators (OBC). In addition, lunar observations are made to independently track VIIRS long‐term calibration stability for the reflective solar bands (RSB). This paper provides an overview of VIIRS OBC functions as well as its on‐orbit operation and calibration activities. It also describes sensor calibration methodologies and demonstrates VIIRS on‐orbit performance from launch to present. Results reported in this paper include on‐orbit changes in sensor spectral band responses, detector noise characterization, and key calibration parameters. Issues identified and their potential impacts on sensor calibration are also discussed. Since launch, the VIIRS instrument nominal operation temperature has been stable to within ±1.0 K. The cold focal plane temperatures have been well controlled, with variations of less than 20 mK over a period of 1.5 years. In general, changes in thermal emissive bands (TEB) detector responses have been less than 0.5%. Despite large response degradation in several near‐infrared and short‐wave infrared bands and large SD degradation at short visible wavelengths, the VIIRS sensor and OBC overall performance has been excellent postlaunch. The degradation caused by the telescope mirror coating contamination has been modeled and its impact addressed through the use of modulated relative spectral response in the improved calibration and the current sensor data record data production. Based on current instrument characteristics and performance, it is expected that the VIIRS calibration will continue to meet its design requirements, including RSB detector signal to noise ratio and TEB detector noise equivalent temperature difference, throughout its 7 year design lifetime.
Key Points
VIIRS on‐orbit calibration methodology
VIIRS onboard calibrators and sensor operation activities
VIIRS on‐orbit performance
Suomi-NPP VIIRS aerosol algorithms and data products Jackson, John M.; Liu, Hongqing; Laszlo, Istvan ...
Journal of geophysical research. Atmospheres,
27 November 2013, Letnik:
118, Številka:
22
Journal Article
Recenzirano
Odprti dostop
The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument on board the Suomi National Polar‐orbiting Partnership (S‐NPP) spacecraft was launched in October 2011. The instrument has 22 spectral ...channels with band centers from 412 nm to 12,050 nm. The VIIRS aerosol data products are derived primarily from the radiometric channels covering the visible through the short‐wave infrared spectral regions (412 nm to 2250 nm). The major components of the VIIRS aerosol retrieval process are data screening, land inversion, ocean inversion, suspended matter typing, and aggregation. The primary data product produced is the aerosol optical thickness (AOT) environmental data record. A higher resolution AOT intermediate product is also produced. These AOT products and their corresponding retrieval algorithms are described in detail, including theoretical basis, retrieval limitations, and data quality flagging. Preliminary evaluation of the data products has been undertaken by the VIIRS aerosol calibration/validation team using Aerosol Robotic Network ground‐based observations to show that the performance of AOT retrievals meets the requirements specified in the Joint Polar Satellite System Level 1 requirements.
Key Points
VIIRS aerosol retrieval algorithms are described in detail
VIIRS aerosol is based on MODIS heritage
VIIRS aerosol data products are available for evaluation
Lounais-Suomen peltoviljelyalueella käytetty perinnönjakostrategia pyrki säilyttämään maatilat jakamattomina ja suosi vanhinta poikaa maatilan jatkajaksi. Perinnönjako kohteli perillisiä ...epätasa-arvoisesti, ja jatkajan sisaruksia uhkasi aleneva säätykierto. Tämä artikkeli käsittelee perinnönjakostrategian sosiaalisia seurauksia väistyvien perillisten kannalta. Jatkajien sisarusten elämänkulkuja seurataan Huittisissa ja Loimaalla 1700- ja 1800-luvuilla. Elämänkulkujen avulla esitetään, minkälaisia mahdollisuuksia ja vaihtoehtoja oli niillä maatilojen lapsilla, jotka eivät jatkaneet kotitilansa emäntänä tai isäntänä. Yli puolet väistyvistä perillisistä päätyi tilallisiksi eli samaan asemaan kuin vanhempansa. Väestönkasvua seurannut taloudellisen ja sosiaalisen eriarvoisuuden lisääntyminen tutkitulla ajalla vaikeutti tilallisasemaan pääsemistä, ja muutos vaikutti erityisesti poikien mahdollisuuksiin. Lisäksi väistyvien perillisten elämään vaikutti kotitilan kameraalinen koko. Suurten tilojen lapsilla oli parhaat mahdollisuudet sosiaalisen aseman säilyttämiseen. Tilan jakaminen perillisten kesken mahdollisti lyhyellä tähtäimellä usealle perilliselle aseman tilallisena, mutta heikensi tilojen talouden perustaa ja siten myös seuraavan sukupolven mahdollisuuksia sijoittua sosiaalisesti hyvään asemaan. 1800-luvulla perinnönjakokäytäntö tuki maanomistuksen keskittymistä, mikä entisestään kiihdytti maaseutuväestön eriarvoistumisen kierrettä. The article focuses on the inheritance practice of peasant farms and its social consequences in Southwest Finland. Holdings were kept undivided and the eldest son had priority in order of succession of the farm. The possibilities and options of other children are studied by following the life course of successor’s siblings in Huittinen and Loimaa in the 18th and 19th centuries. More than a half of the non-succeeding siblings managed to become farmers in some other way. Population growth increased economic and social inequality during the period and made it more difficult to maintain the social position, especially for sons. In addition to gender, social success was influenced by the economic features of the home farm. Children from large farms maintained social position most likely. The partitioning of the farm between two or more heirs weakened the economy of the farms and the possibilities of the next generation to reach a socially desirable position. Instead, the possibilities of the offspring were improved by acquiring several holdings, so that the concentration of land ownership accelerated the cycle of inequality.
NASA's Black Marble nighttime lights product suite (VNP46) is available at 500 m resolution since January 2012 with data from the Visible Infrared Imaging Radiometer Suite (VIIRS) Day/Night Band ...(DNB) onboard the Suomi National Polar-orbiting Platform (SNPP). The retrieval algorithm, developed and implemented for routine global processing at NASA's Land Science Investigator-led Processing System (SIPS), utilizes all high-quality, cloud-free, atmospheric-, terrain-, vegetation-, snow-, lunar-, and stray light-corrected radiances to estimate daily nighttime lights (NTL) and other intrinsic surface optical properties. Key algorithm enhancements include: (1) lunar irradiance modeling to resolve non-linear changes in phase and libration; (2) vector radiative transfer and lunar bidirectional surface anisotropic reflectance modeling to correct for atmospheric and BRDF effects; (3) geometric-optical and canopy radiative transfer modeling to account for seasonal variations in NTL; and (4) temporal gap-filling to reduce persistent data gaps. Extensive benchmark tests at representative spatial and temporal scales were conducted on the VNP46 time series record to characterize the uncertainties stemming from upstream data sources. Initial validation results are presented together with example case studies illustrating the scientific utility of the products. This includes an evaluation of temporal patterns of NTL dynamics associated with urbanization, socioeconomic variability, cultural characteristics, and displaced populations affected by conflict. Current and planned activities under the Group on Earth Observations (GEO) Human Planet Initiative are aimed at evaluating the products at different geographic locations and time periods representing the full range of retrieval conditions.
•NASA's Black Marble product suite (VNP46) is being produced at 500 m resolution.•VNP46 delivers daily global data to characterize Human-Earth system interactions.•Nighttime lights are corrected for atmospheric, BRDF, and seasonal effects.•This results in larger noise reduction levels compared to top-of-atmosphere data.•The product enables tracking of vulnerable populations in conflict-affected areas.
A mountain wave with a significant brightness temperature amplitude and ~500 km horizontal wavelength was observed over the Andes on 24–25 July 2017 in Atmospheric Infrared Sounder (AIRS)/Aqua ...satellite data. In the Modern‐Era Retrospective Analysis for Research and Applications, version 2 (MERRA‐2), reanalysis data, the intense eastward wind flowed over the Andes. Visible/Infrared Imaging Radiometer Suite (VIIRS)/Suomi‐NPP (National Polar‐orbiting Partnership) did not detect the mountain waves; however, it observed concentric ring‐like waves in the nightglow emissions at ~87 km with ~100 km wavelengths on the same night over and leeward of the Southern Andes. A ray tracing analysis showed that the mountain waves propagated to the east of the Andes, where concentric ring‐like waves appeared above a region of mountain wave breaking. Therefore, the concentric ring‐like waves were likely secondary waves generated by momentum deposition that accompanied mountain wave breaking. These results provide the first direct evidence for secondary gravity waves generated by momentum deposition.
Plain Language Summary
A recent model study (Vadas & Becker, 2019, https://doi.org/10.1029/2019JA026694) showed that mountain waves created over the Andes broke in the stratosphere and mesosphere, thereby depositing their momentum and creating “secondary” gravity waves. These waves then propagated into the lower thermosphere and created tertiary (or higher‐order) waves, some of which propagated to the upper thermosphere. This vertical multistep coupling mechanism is likely important for creating ionospheric disturbances in the F region. However, observational evidence supporting this mechanism is lacking. The purpose of this study is to show observational evidence using data from two satellite instruments: AIRS/Aqua and VIIRS/Suomi‐NPP. AIRS captured a mountain wave with a significant amplitude in the stratosphere over the Andes on 24–25 July 2017. VIIRS/Suomi‐NPP did not detect the mountain waves but instead observed concentric ring‐like gravity waves in the mesosphere on the leeward of the Andes. The concentric ring‐like structure is one of the features of secondary waves created from momentum deposition that accompanies breaking gravity waves; thus, we conclude that the observed gravity waves were likely secondary gravity waves. These observational results provide the first direct evidence for secondary gravity waves generated by momentum deposition from breaking mountain waves and support the vertical multistep coupling mechanism.
Key Points
VIIRS captured nightglow concentric ring‐like gravity waves in the mesopause east of Southern Andes during intense winter mountain wave event
Mountain waves observed by AIRS likely broke while the waves were propagating upward and eastward
Concentric ring‐like gravity waves captured by VIIRS were likely generated by local body forces created by mountain wave breaking
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