Solar Radiation Modification: a multi-century commitment

2021 ◽  
Author(s):  
Susanne Baur ◽  
Alexander Nauels ◽  
Carl-Friedrich Schleussner
Keyword(s):  
Side Effects ◽  
Solar Radiation ◽  
Large Scale ◽  
Climate Model ◽  
Radiation Modification ◽  
Emissions Scenarios ◽  
Negative Side Effects ◽  
Cumulative Risks ◽  
Lock In ◽  
Phase Out

<p>A growing body of literature investigates the effects of Solar Radiation Modification (SRM) on global and regional climates. Previous studies on SRM have mainly focused on potentials and side effects of deployment without addressing plausible avenues of a subsequent phase-out. This would require large-scale carbon dioxide removal (CDR). Here, we look at SRM deployment lengths to keep global temperature increase to 1.5°C under three emissions scenarios that follow current climate policies until 2100 and are continued with varying assumptions about the magnitude of net-negative CDR (-11.5, -10 and -5 GtCO<sub>2</sub>yr<sup>-1</sup>). Our results show that there would be a lock-in of around 245 - 315 years of continuous SRM engagement. During peak deployment in 2125 around 2.80 Wm<sup>-2</sup> would have to be compensated by SRM, a number at the upper end of currently estimated maximum SRM potential in climate model environments. In total, around 976 - 1344 GtCO<sub>2</sub>would need to be removed from the atmosphere via CDR. We find only minor effects of SRM on carbon fluxes a few decades after cessation. Our study shows that even if SRM is combined with high CDR, SRM would come with very long legacies of deployment, implying centuries of costs, cumulative risks and all negative side effects of SRM and CDR combined. </p>

scholarly journals Side Effects of Large-Scale Assessments in Education

2019 ◽  
Vol 2 (3) ◽  
pp. 279-296 ◽  
Author(s):  
Trina E. Emler ◽  
Yong Zhao ◽  
Jiayi Deng ◽  
Danqing Yin ◽  
Yurou Wang
Keyword(s):  
Side Effects ◽  
Thematic Analysis ◽  
Large Scale ◽  
Review Of The Literature ◽  
Present Evidence ◽  
Negative Side ◽  
Innovation In Education ◽  
Large Scale Assessments ◽  
Research In Education ◽  
Negative Side Effects

Purpose: In line with a recent call for side effects research in education, this article aims to synthesize the major concerns that have been raised in the literature concerning large-scale assessments (LSAs) in education. Design/Approach/Methods: The researchers endeavored to complete a deep review of the literature on LSAs to synthesize the reported side effects. The review was synthesized thematically to understand and report the consequences of the ongoing push for the use of LSA in education. Findings: Thematic analysis indicated overarching side effects of LSA in education. We discuss why negative side effects exist and present evidence of the most commonly observed side effects of LSA in education, including distorting education, exacerbating inequity and injustice, demoralization of professionals, ethical corruption, and stifling of innovation in education. Originality/Value: While concerns about the use and misuse of LSA in education are not new and have been discussed widely in the literature, rarely have they been discussed as inherent qualities and consequences of LSAs that can do harm to education.

scholarly journals Side effects and accounting aspects of hypothetical large-scale Southern Ocean iron fertilization

2010 ◽  
Vol 7 (2) ◽  
pp. 2949-2995 ◽  
Author(s):  
A. Oschlies ◽  
W. Koeve ◽  
W. Rickels ◽  
K. Rehdanz
Keyword(s):  
Carbon Sequestration ◽  
Side Effects ◽  
Southern Ocean ◽  
Atmospheric Carbon Dioxide ◽  
Large Scale ◽  
Climate Model ◽  
N2o Emissions ◽  
Co2 Fluxes ◽  
Iron Fertilization ◽  
Fertilization Experiments

Abstract. Recent suggestions to slow down the increase in atmospheric carbon dioxide have included ocean fertilization by addition of the micronutrient iron to Southern Ocean surface waters, where a number of natural and artificial iron fertilization experiments have shown that low ambient iron concentrations limit phytoplankton growth. Using a coupled carbon-climate model with the marine biology's response to iron addition calibrated against data from natural iron fertilization experiments, we examine biogeochemical side effects of a hypothetical large-scale Southern Ocean Iron Fertilization (OIF) that need to be considered when attempting to account for possible OIF-induced carbon offsets. In agreement with earlier studies our model simulates an OIF-induced increase in local air-sea CO2 fluxes by about 60 GtC over a 100-year period, which amounts to about 40% of the OIF-induced increase in organic carbon export. Offsetting CO2 return fluxes outside the region and after stopping the fertilization at 1, 7, 10, 50, and 100 years are quantified for a typical accounting period of 100 years. For continuous Southern Ocean iron fertilization, the return flux outside the fertilized area cancels about 8% of the fertilization-induced CO2 air-sea flux within the fertilized area on a 100-yr timescale. This "leakage" effect has a similar radiative impact as the simulated enhancement of marine N2O emissions. Other side effects not yet discussed in terms of accounting schemes include a decrease in Southern Ocean oxygen levels and a simultaneous shrinking of tropical suboxic areas, and accelerated ocean acidification in the entire water column in the Southern Ocean on the expense of reduced globally averaged surface water acidification. A prudent approach to account for the OIF-induced carbon sequestration would account for global air-sea CO2 fluxes rather than for local fluxes into the fertilized area only. However, according to our model, this would underestimate the potential for offsetting CO2 emissions by about 20% on a 100 year accounting timescale. We suggest that a fair accounting scheme applicable to both terrestrial and marine carbon sequestration has to be based on emission offsets rather than on changes in individual carbon pools.

scholarly journals Side effects and accounting aspects of hypothetical large-scale Southern Ocean iron fertilization

2010 ◽  
Vol 7 (12) ◽  
pp. 4017-4035 ◽  
Author(s):  
A. Oschlies ◽  
W. Koeve ◽  
W. Rickels ◽  
K. Rehdanz
Keyword(s):  
Carbon Sequestration ◽  
Side Effects ◽  
Southern Ocean ◽  
Atmospheric Carbon Dioxide ◽  
Large Scale ◽  
Climate Model ◽  
N2o Emissions ◽  
Co2 Fluxes ◽  
Iron Fertilization ◽  
Fertilization Experiments

Abstract. Recent suggestions to slow down the increase in atmospheric carbon dioxide have included ocean fertilization by addition of the micronutrient iron to Southern Ocean surface waters, where a number of natural and artificial iron fertilization experiments have shown that low ambient iron concentrations limit phytoplankton growth. Using a coupled carbon-climate model with the marine biology's response to iron addition calibrated against data from natural iron fertilization experiments, we examine biogeochemical side effects of a hypothetical large-scale Southern Ocean Iron Fertilization (OIF) that need to be considered when attempting to account for possible OIF-induced carbon offsets. In agreement with earlier studies our model simulates an OIF-induced increase in local air-sea CO2 fluxes by about 73 GtC over a 100-year period, which amounts to about 48% of the OIF-induced increase in organic carbon export out of the fertilized area. Offsetting CO2 return fluxes outside the region and after stopping the fertilization at 1, 7, 10, 50, and 100 years are quantified for a typical accounting period of 100 years. For continuous Southern Ocean iron fertilization, the CO2 return flux outside the fertilized area cancels about 20% of the fertilization-induced CO2 air-sea flux within the fertilized area on a 100-yr timescale. This "leakage" effect has a radiative impact more than twice as large as the simulated enhancement of marine N2O emissions. Other side effects not yet discussed in terms of accounting schemes include a decrease in Southern Ocean oxygen levels and a simultaneous shrinking of tropical suboxic areas, and accelerated ocean acidification in the entire water column in the Southern Ocean at the expense of reduced globally-averaged surface-water acidification. A prudent approach to account for the OIF-induced carbon sequestration would account for global air-sea CO2 fluxes rather than for local fluxes into the fertilized area only. However, according to our model, this would underestimate the potential for offsetting CO2 emissions by about 20% on a 100 year accounting timescale. We suggest that a fair accounting scheme applicable to both terrestrial and marine carbon sequestration has to be based on emission offsets rather than on changes in individual carbon pools.

GISS Model E2.2: A Climate Model Optimized for the Middle Atmosphere—2. Validation of Large‐Scale Transport and Evaluation of Climate Response

2020 ◽  
Vol 125 (24) ◽  
Author(s):  
Clara Orbe ◽  
David Rind ◽  
Jeffrey Jonas ◽  
Larissa Nazarenko ◽  
Greg Faluvegi ◽  
...  
Keyword(s):  
Large Scale ◽  
Climate Model ◽  
Middle Atmosphere ◽  
Climate Response

Flexible Spectrum Management: Approaches for India

2015 ◽  
Vol 8 (1) ◽  
Author(s):  
Arturo Basaure ◽  
Heikki Kokkinen ◽  
Heikki Hämmäinen ◽  
V. Sridhar
Keyword(s):  
Large Scale ◽  
Mobile Services ◽  
Radio Spectrum ◽  
Spectrum Management ◽  
Management Approach ◽  
Unlicensed Spectrum ◽  
Spectrum Band ◽  
Management Policies ◽  
Management Approaches ◽  
Lock In

Radio spectrum for commercial mobile services continues to be scarce. Countries around the world have recognized the importance of efficient utilization of this scarce resource and have initiated regulatory and policy steps towards flexible approaches to spectrum management, including sharing of licensed spectrum, and releasing unlicensed spectrum for mobile services. Technologies for shared access and the associated standardization activities have also progressed towards possible large scale deployments. In this paper, we analyze the evolution of spectrum management policies using a causal model and indicate how the markets can lock in to either centralized or flexible approach. We also cite a use case of a flexible spectrum management approach using spectrum band fill option and indicate its suitability to the Indian context.

scholarly journals A Digital Framework to Predict the Sunshine Requirements of Landscape Plants

2021 ◽  
Vol 11 (5) ◽  
pp. 2098
Author(s):  
Heyi Wei ◽  
Wenhua Jiang ◽  
Xuejun Liu ◽  
Bo Huang
Keyword(s):  
Solar Radiation ◽  
Plant Species ◽  
Large Scale ◽  
Normal Growth ◽  
Adaptive Selection ◽  
Landscape Plant ◽  
Landscape Plants ◽  
The Stability ◽  
Stability And Accuracy ◽  
The City

Knowledge of the sunshine requirements of landscape plants is important information for the adaptive selection and configuration of plants for urban greening, and is also a basic attribute of plant databases. In the existing studies, the light compensation point (LCP) and light saturation point (LSP) have been commonly used to indicate the shade tolerance for a specific plant; however, these values are difficult to adopt in practice because the landscape architect does not always know what range of solar radiation is the best for maintaining plant health, i.e., normal growth and reproduction. In this paper, to bridge the gap, we present a novel digital framework to predict the sunshine requirements of landscape plants. First, the research introduces the proposed framework, which is composed of a black-box model, solar radiation simulation, and a health standard system for plants. Then, the data fitting between solar radiation and plant growth response is used to obtain the value of solar radiation at different health levels. Finally, we adopt the LI-6400XT Portable Photosynthetic System (Li-Cor Inc., Lincoln, NE, USA) to verify the stability and accuracy of the digital framework through 15 landscape plant species of a residential area in the city of Wuhan, China, and also compared and analyzed the results of other researchers on the same plant species. The results show that the digital framework can robustly obtain the values of the healthy, sub-healthy, and unhealthy levels for the 15 landscape plant species. The purpose of this study is to provide an efficient forecasting tool for large-scale surveys of plant sunshine requirements. The proposed framework will be beneficial for the adaptive selection and configuration of urban plants and will facilitate the construction of landscape plant databases in future studies.

scholarly journals Impact of Liposomal Drug Formulations on the RBCs Shape, Transmembrane Potential, and Mechanical Properties

2021 ◽  
Vol 22 (4) ◽  
pp. 1710
Author(s):  
Sylwia Cyboran-Mikołajczyk ◽  
Przemysław Sareło ◽  
Robert Pasławski ◽  
Urszula Pasławska ◽  
Magdalena Przybyło ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Side Effects ◽  
Blood Cells ◽  
Transmembrane Potential ◽  
Drug Formulations ◽  
Liposomal Drug ◽  
Irregular Shapes ◽  
Liposomal Formulations ◽  
Current Therapies ◽  
Negative Side Effects

Liposomal technologies are used in order to improve the effectiveness of current therapies or to reduce their negative side effects. However, the liposome–erythrocyte interaction during the intravenous administration of liposomal drug formulations may result in changes within the red blood cells (RBCs). In this study, it was shown that phosphatidylcholine-composed liposomal formulations of Photolon, used as a drug model, significantly influences the transmembrane potential, stiffness, as well as the shape of RBCs. These changes caused decreasing the number of stomatocytes and irregular shapes proportion within the cells exposed to liposomes. Thus, the reduction of anisocytosis was observed. Therefore, some nanodrugs in phosphatidylcholine liposomal formulation may have a beneficial effect on the survival time of erythrocytes.

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