scholarly journals Carbon Emissions and Removals by Forests: New Estimates 1990–2020

2020 ◽  
Author(s):  
Francesco N. Tubiello ◽  
Anssi Pekkarinen ◽  
Lars Marklund ◽  
Nathan Wanner ◽  
Giulia Conchedda ◽  
...  

Abstract. Trends in global, regional and national CO2 emissions and removals from forest for the period 1990–2020, are estimated for the first time using data from the Forest Resources Assessment (FRA) 2020, providing new information with respect to the previous FRA 2015. Estimates indicate significant reduction of deforestation emissions over the study period, albeit more slowly than previously assessed, from an average of 4.3 Gt CO2 yr−1 during 1991–2000, to an average of 2.9 Gt CO2 yr−1 during 2016–2020. Remaining forest land was a significant net carbon sink globally and over the entire period, albeit decreasing in strength, from −3.4 Gt CO2 yr−1 in 1991–2000 to −2.5 Gt CO2 yr−1 during 2016–2020. The overall net contribution of forests to atmospheric CO2(i.e., the combined effect of deforestation and forest emissions/removals) was an overall emission source of roughly 0.4 Gt CO2 yr−1 on average during 1991–2020, more than one-third less than previously estimated. Remarkably, the new data also suggest an overall net sink of about −0.7 Gt CO2 yr−1 during 2011–2015, never reported before. Forest emissions/removals data independently reported by countries to the United Nations Framework on Climate Change were in excellent agreement with the FAO estimates over the entire period 1990–2020, confirming a large sink on forest land estimated for 2011–2015. Data are made available as open access via the Zenodo portal (Tubiello, 2020), with DOI 10.5281/zenodo.3941973.

2021 ◽  
Vol 13 (4) ◽  
pp. 1681-1691
Author(s):  
Francesco N. Tubiello ◽  
Giulia Conchedda ◽  
Nathan Wanner ◽  
Sandro Federici ◽  
Simone Rossi ◽  
...  

Abstract. National, regional and global CO2 emissions and removals from forests were estimated for the period 1990–2020 using as input the country reports of the Global Forest Resources Assessment 2020. The new Food and Agriculture Organization of the United Nations (FAO) estimates, based on a simple carbon stock change approach, update published information on net emissions and removals from forests in relation to (a) net forest conversion and (b) forest land. Results show a significant reduction in global emissions from net forest conversion over the study period, from a mean of 4.3 in 1991–2000 to 2.9 Gt CO2 yr−1 in 2016–2020. At the same time, forest land was a significant carbon sink globally but decreased in strength over the study period, from −3.5 to −2.6 Gt CO2 yr−1. Combining net forest conversion with forest land, our estimates indicated that globally forests were a small net source of CO2 to the atmosphere on average during 1990–2020, with mean net emissions of 0.4 Gt CO2 yr−1. The exception was the brief period 2011–2015, when forest land removals counterbalanced emissions from net forest conversion, resulting in a global net sink of −0.7 Gt CO2 yr−1. Importantly, the new estimates allow for the first time in the literature the characterization of forest emissions and removals for the decade just concluded, 2011–2020, showing that in this period the net contribution of forests to the atmosphere was very small, i.e., a sink of less than −0.2 Gt CO2 yr−1 – an estimate not yet reported in the literature. This near-zero balance was nonetheless the result of large global fluxes of opposite sign, namely net forest conversion emissions of 3.1 Gt CO2 yr−1 counterbalanced by net removals on forest land of −3.3 Gt CO2 yr−1. Finally, we compared our estimates with data independently reported by countries to the United Nations Framework on Climate Change, indicating close agreement between FAO and country emissions and removals estimates. Data from this study are openly available via the Zenodo portal (Tubiello, 2020), with DOI https://doi.org/10.5281/zenodo.3941973, as well as in the FAOSTAT (Food and Agriculture Organization Corporate Statistical Database) emissions database (FAO, 2021a).


2017 ◽  
Vol 44 (1) ◽  
pp. 103-109 ◽  
Author(s):  
M. A. Taylor

A manuscript memoir of Hugh Miller (1802–1856), geologist, writer and newspaper editor, is attributed to his son Hugh Miller FGS (1850–1896). It is published here, apparently for the first time. It was written sometime in 1881–1896, more probably 1882–1895. Its intended place of publication is discussed. It is an interesting contribution to Miller biography, written by a family member and providing some new information and anecdotes.


Geosciences ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 321
Author(s):  
Miltiadis Polidorou ◽  
Niki Evelpidou ◽  
Theodora Tsourou ◽  
Hara Drinia ◽  
Ferréol Salomon ◽  
...  

Akrotiri Salt Lake is located 5 km west of the city of Lemesos in the southernmost part of the island of Cyprus. The evolution of the Akrotiri Salt Lake is of great scientific interest, occurring during the Holocene when eustatic and isostatic movements combined with local active tectonics and climate change developed a unique geomorphological environment. The Salt Lake today is a closed lagoon, which is depicted in Venetian maps as being connected to the sea, provides evidence of the geological setting and landscape evolution of the area. In this study, for the first time, we investigated the development of the Akrotiri Salt Lake through a series of three cores which penetrated the Holocene sediment sequence. Sedimentological and micropaleontological analyses, as well as geochronological studies were performed on the deposited sediments, identifying the complexity of the evolution of the Salt Lake and the progressive change of the area from a maritime space to an open bay and finally to a closed salt lake.


2021 ◽  
Vol 63 (4) ◽  
pp. 408-415
Author(s):  
Maria Rubio Juan ◽  
Melanie Revilla

The presence of satisficers among survey respondents threatens survey data quality. To identify such respondents, Oppenheimer et al. developed the Instructional Manipulation Check (IMC), which has been used as a tool to exclude observations from the analyses. However, this practice has raised concerns regarding its effects on the external validity and the substantive conclusions of studies excluding respondents who fail an IMC. Thus, more research on the differences between respondents who pass versus fail an IMC regarding sociodemographic and attitudinal variables is needed. This study compares respondents who passed versus failed an IMC both for descriptive and causal analyses based on structural equation modeling (SEM) using data from an online survey implemented in Spain in 2019. These data were analyzed by Rubio Juan and Revilla without taking into account the results of the IMC. We find that those who passed the IMC do differ significantly from those who failed for two sociodemographic and five attitudinal variables, out of 18 variables compared. Moreover, in terms of substantive conclusions, differences between those who passed and failed the IMC vary depending on the specific variables under study.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Matieu Henry ◽  
Zaheer Iqbal ◽  
Kristofer Johnson ◽  
Mariam Akhter ◽  
Liam Costello ◽  
...  

Abstract Background National forest inventory and forest monitoring systems are more important than ever considering continued global degradation of trees and forests. These systems are especially important in a country like Bangladesh, which is characterised by a large population density, climate change vulnerability and dependence on natural resources. With the aim of supporting the Government’s actions towards sustainable forest management through reliable information, the Bangladesh Forest Inventory (BFI) was designed and implemented through three components: biophysical inventory, socio-economic survey and remote sensing-based land cover mapping. This article documents the approach undertaken by the Forest Department under the Ministry of Environment, Forests and Climate Change to establish the BFI as a multipurpose, efficient, accurate and replicable national forest assessment. The design, operationalization and some key results of the process are presented. Methods The BFI takes advantage of the latest and most well-accepted technological and methodological approaches. Importantly, it was designed through a collaborative process which drew from the experience and knowledge of multiple national and international entities. Overall, 1781 field plots were visited, 6400 households were surveyed, and a national land cover map for the year 2015 was produced. Innovative technological enhancements include a semi-automated segmentation approach for developing the wall-to-wall land cover map, an object-based national land characterisation system, consistent estimates between sample-based and mapped land cover areas, use of mobile apps for tree species identification and data collection, and use of differential global positioning system for referencing plot centres. Results Seven criteria, and multiple associated indicators, were developed for monitoring progress towards sustainable forest management goals, informing management decisions, and national and international reporting needs. A wide range of biophysical and socioeconomic data were collected, and in some cases integrated, for estimating the indicators. Conclusions The BFI is a new information source tool for helping guide Bangladesh towards a sustainable future. Reliable information on the status of tree and forest resources, as well as land use, empowers evidence-based decision making across multiple stakeholders and at different levels for protecting natural resources. The integrated socio-economic data collected provides information about the interactions between people and their tree and forest resources, and the valuation of ecosystem services. The BFI is designed to be a permanent assessment of these resources, and future data collection will enable monitoring of trends against the current baseline. However, additional institutional support as well as continuation of collaboration among national partners is crucial for sustaining the BFI process in future.


2021 ◽  
Vol 3 (6) ◽  
Author(s):  
César de Oliveira Ferreira Silva ◽  
Mariana Matulovic ◽  
Rodrigo Lilla Manzione

Abstract Groundwater governance uses modeling to support decision making. Therefore, data science techniques are essential. Specific difficulties arise because variables must be used that cannot be directly measured, such as aquifer recharge and groundwater flow. However, such techniques involve dealing with (often not very explicitly stated) ethical questions. To support groundwater governance, these ethical questions cannot be solved straightforward. In this study, we propose an approach called “open-minded roadmap” to guide data analytics and modeling for groundwater governance decision making. To frame the ethical questions, we use the concept of geoethical thinking, a method to combine geoscience-expertise and societal responsibility of the geoscientist. We present a case study in groundwater monitoring modeling experiment using data analytics methods in southeast Brazil. A model based on fuzzy logic (with high expert intervention) and three data-driven models (with low expert intervention) are tested and evaluated for aquifer recharge in watersheds. The roadmap approach consists of three issues: (a) data acquisition, (b) modeling and (c) the open-minded (geo)ethical attitude. The level of expert intervention in the modeling stage and model validation are discussed. A search for gaps in the model use is made, anticipating issues through the development of application scenarios, to reach a final decision. When the model is validated in one watershed and then extrapolated to neighboring watersheds, we found large asymmetries in the recharge estimatives. Hence, we can show that more information (data, expertise etc.) is needed to improve the models’ predictability-skill. In the resulting iterative approach, new questions will arise (as new information comes available), and therefore, steady recourse to the open-minded roadmap is recommended. Graphic abstract


2011 ◽  
Vol 29 (6) ◽  
pp. 1197-1208 ◽  
Author(s):  
G. Wannberg ◽  
A. Westman ◽  
A. Pellinen-Wannberg

Abstract. The polarization characteristics of 930-MHz meteor head echoes have been studied for the first time, using data obtained in a series of radar measurements carried out with the tristatic EISCAT UHF high power, large aperture (HPLA) radar system in October 2009. An analysis of 44 tri-static head echo events shows that the polarization of the echo signal recorded by the Kiruna receiver often fluctuates strongly on time scales of tens of microseconds, illustrating that the scattering process is essentially stochastic. On longer timescales (> milliseconds), more than 90 % of the recorded events show an average polarization signature that is independent of meteor direction of arrival and echo strength and equal to that of an incoherent-scatter return from underdense plasma filling the tristatic observation volume. This shows that the head echo plasma targets scatter isotropically, which in turn implies that they are much smaller than the 33-cm wavelength and close to spherically symmetric, in very good agreement with results from a previous EISCAT UHF study of the head echo RCS/meteor angle-of-incidence relationship. Significant polarization is present in only three events with unique target trajectories. These all show a larger effective target cross section transverse to the trajectory than parallel to it. We propose that the observed polarization may be a signature of a transverse charge separation plasma resonance in the region immediately behind the meteor head, similar to the resonance effects previously discussed in connection with meteor trail echoes by Herlofson, Billam and Browne, Jones and Jones and others.


2017 ◽  
Vol 10 (5) ◽  
pp. 662-686
Author(s):  
Dimitrios Staikos ◽  
Wenjun Xue

Purpose With this paper, the authors aim to investigate the drivers behind three of the most important aspects of the Chinese real estate market, housing prices, housing rent and new construction. At the same time, the authors perform a comprehensive empirical test of the popular 4-quadrant model by Wheaton and DiPasquale. Design/methodology/approach In this paper, the authors utilize panel cointegration estimation methods and data from 35 Chinese metropolitan areas. Findings The results indicate that the 4-quadrant model is well suited to explain the determinants of housing prices. However, the same is not true regarding housing rent and new construction suggesting a more complex theoretical framework may be required for a well-rounded explanation of real estate markets. Originality/value It is the first time that panel data are used to estimate rent and new construction for China. Also, it is the first time a comprehensive test of the Wheaton and DiPasquale 4-quadrant model is performed using data from China.


2001 ◽  
Vol 15 (17n19) ◽  
pp. 683-687
Author(s):  
A. SILVA-CASTILLO ◽  
F. PEREZ-RODRIGUEZ

We have applied the 45° reflectometry for the first time to study exciton-polaritons in quantum wells. The 45° reflectometry is a new polarization-modulation technique, which is based on the measurement of the difference [Formula: see text] between the p-polarization reflectivity (Rp) and the squared s-polarization reflectivity [Formula: see text] at an angle of incidence of 45°. We show that [Formula: see text] spectra may provide qualitatively new information on the exciton-polariton modes in a quantum well. These optical spectra turn out to be very sensitive to the zeros of the dielectric function along the quantum-well growth direction and, therefore, allow to identify the resonances associated with the Z exciton-polariton mode. We demonstrate that 45° reflectometry could be a powerful tool for studying Z exciton-polariton modes in near-surface quantum wells, which are difficult to observe in simple spectra of reflectivity Rp


Nematology ◽  
2021 ◽  
pp. 1-23
Author(s):  
Mei Na Liu ◽  
Yu Mei Xu ◽  
Zeng Qi Zhao ◽  
Jian Ming Wang

Summary This paper describes a new species of Bastiania, presents a new record and redescribes a known species of Tripyla. These nematodes are all in the order Triplonchida and were collected from Shanxi Province, North China. Bastiania sinensis sp. n. is characterised by having the female with a relatively slender body 1049-1295 μm long, dorsally arcuate after heat relaxation, with outer labial setae and cephalic setae in a single circle, an oval amphid, 7-8 laterodorsal cervical setae scattered in the pharyngeal region, orthometamenes and pseudocoelomocytes present, tail conoid with a mucron 1-2 μm long, two pairs of caudal setae present, a = 58.1-75.5, b = 4.0-4.6, c = 12.7-19.7, c′ = 4.1-7.8 and V = 61.1-67.7. Males were not found. Tripyla aquatica is recorded for the first time from China, and is redescribed. Tripyla setifera has been reported from China but without a detailed description – now provided. In addition, phylogenetic relationships among the species were analysed using data from the near full length small subunit (SSU) and D2-D3 segments of large subunit (LSU) of rRNA genes. Bastiania sinensis sp. n. is monophyletic with the Bastiania sequences available in GenBank, but is on an independent branch supporting its status as a separate species; T. aquatica and T. setifera are monophyletically clustered with known Tripyla species and grouped together with sequences from their respective species.


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