Planet Earth

2020 ◽  
pp. 1-38
Author(s):  
John Evans
Keyword(s):  
Molecular Structure ◽  
Global Warming ◽  
Energy Balance ◽  
Atmospheric Chemistry ◽  
Radiative Forcing ◽  
Fossil Fuels ◽  
Residence Times ◽  
Atmospheric Gases ◽  
Energy Demands ◽  
Atmospheric Concentrations

The pressure on planetary resources is substantially driven by increases in energy demands that have been mostly met by the combustion of fossil fuels. The basis of the warming in the troposphere is explained starting from the molecular structure of atmospheric components and their resulting rotational and vibrational spectra. From the absorptions in the infrared, the radiative efficiencies of atmospheric gases can be established. The residence times of gases in the atmosphere is explained on the basis of their atmospheric chemistry. Taking these factors together with atmospheric concentrations, the Global-Warming and -Temperature Potentials can be derived. The overall energy balance in the atmosphere is shown and the resulting net radiative forcing. The principle of the sustainability triangle is explained showing that reduction in radiative forcing may be achievable by a summation of contributions.

Communities self-sufficient in fuels for humans,transport and electrical needs

2011 ◽  
pp. 466-470
Author(s):  
Peter Charles Jais
Keyword(s):  
Global Warming ◽  
Energy Balance ◽  
Fossil Fuels ◽  
Electrical Energy ◽  
The Self ◽  
Small Community ◽  
Renewable Biomass ◽  
Automotive Fuel ◽  
Self Sufficiency ◽  
The World

In view of the present problems facing the world with respect to fossil fuels (pollution and global warming, availability and price), the possibility was studied of a small community becoming self-sufficient in sugar, automotive fuel (ethanol) and electricity, all from renewable biomass (sugarcane). The study was carried out, based on a real project that is presently installed on similar lines. The fuel needs of a community of 100,000 people were quantified in terms of sugar, ethanol, and electricity. A mass and energy balance was calculated to determine the amounts of cane and trash needed to produce the sugar, ethanol and electricity by generation and cogeneration. The results showed that 100 t of cane per hour can supply sufficient sugar and electrical energy for a community of 100,000 people and run their cars on 96% (by volume) ethanol (no mix with gasoline) and still be able to export surplus ethanol. The self-sufficiency is for the whole year and not only the crop period. The overall results show that, when compared with the importation of ‘fuels’, the project is positive.

Attributing the negative scaling of extreme precipitation with temperature over India to cloud radiative cooling during the monsoon season

2021 ◽  
Author(s):  
Sarosh Alam Ghausi ◽  
Axel Kleidon ◽  
Subimal Ghosh
Keyword(s):  
Global Warming ◽  
Energy Balance ◽  
Extreme Precipitation ◽  
Radiative Forcing ◽  
Monsoon Season ◽  
Maximum Power ◽  
Radiative Cooling ◽  
Tropical Regions ◽  
Clear Sky ◽  
Surface Temperatures

<p>Extreme precipitation is expected to increase at the rate of 7% per degree rise in temperature as suggested by the Clausius-Clapeyron equation (also known as CC scaling). Observations however, show deviations from the CC rate, with mostly negative precipitation - temperature scaling in warm tropical regions. Here we explain the negative precipitation scaling in the tropics with the cloud radiative effect on surface temperatures. Temperatures are shaped by the surface energy balance, which is affected by clouds, and hence temperatures are not independent of precipitation. We used observations from India and found negative scaling rates over most regions as extreme precipitation scaling tends to breakdown at temperatures of about 23◦to 25◦C. We show that these negative scaling rates arise from the radiative cooling of clouds associated with precipitation events which is predominant in India during the summer monsoon season. To test our hypothesis, we used an energy balance model constrained by assumption that convective exchange within atmosphere works at its thermodynamic limit of maximum power. Using the NASA-CERES radiation product, we calculated surface temperatures for “All sky” and “Clear sky” conditions to include/exclude the effect of cloud radiative forcing. Our results show a diametric change in precipitation scaling after removing the cooling effect of clouds on surface temperatures. Negative precipitation scaling (-4% /◦C) was found when using “All sky” conditions, but these come close to the CC rate (7% to 9% /◦C) when estimated using temperatures derived from “Clear sky” conditions. The breakdown in extreme precipitation scaling at high temperatures also disappeared forthe “Clear sky” temperatures. This implies that the breakdown in scaling may not relate to changes in aridity or the lack of moisture, but rather to the associated changes in cloud cover. Negative scaling rates derived from observations are thus likely to misrepresent the response of extreme precipitation to global warming in tropical regions. Our findings suggest that an intensification of precipitation extremes at CC rate with global warming is consistent with observations.</p><p>Keywords: Extreme Precipitation, CC scaling, Maximum Power, Indian Mon-soon</p>

scholarly journals Long-lived halocarbon trends and budgets from atmospheric chemistry modelling constrained with measurements in polar firn

2009 ◽  
Vol 9 (12) ◽  
pp. 3911-3934 ◽  
Author(s):  
P. Martinerie ◽  
E. Nourtier-Mazauric ◽  
J.-M. Barnola ◽  
W. T. Sturges ◽  
D. R. Worton ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Radiative Forcing ◽  
Numerical Models ◽  
Atmospheric Model ◽  
Calculated Concentration ◽  
Low Concentrations ◽  
Radiative Model ◽  
Green Function Approach ◽  
Atmospheric Concentrations ◽  
Depth Concentration

Abstract. The budgets of seven halogenated gases (CFC-11, CFC-12, CFC-113, CFC-114, CFC-115, CCl4 and SF6) are studied by comparing measurements in polar firn air from two Arctic and three Antarctic sites, and simulation results of two numerical models: a 2-D atmospheric chemistry model and a 1-D firn diffusion model. The first one is used to calculate atmospheric concentrations from emission trends based on industrial inventories; the calculated concentration trends are used by the second one to produce depth concentration profiles in the firn. The 2-D atmospheric model is validated in the boundary layer by comparison with atmospheric station measurements, and vertically for CFC-12 by comparison with balloon and FTIR measurements. Firn air measurements provide constraints on historical atmospheric concentrations over the last century. Age distributions in the firn are discussed using a Green function approach. Finally, our results are used as input to a radiative model in order to evaluate the radiative forcing of our target gases. Multi-species and multi-site firn air studies allow to better constrain atmospheric trends. The low concentrations of all studied gases at the bottom of the firn, and their consistency with our model results confirm that their natural sources are small. Our results indicate that the emissions, sinks and trends of CFC-11, CFC-12, CFC-113, CFC-115 and SF6 are well constrained, whereas it is not the case for CFC-114 and CCl4. Significant emission-dependent changes in the lifetimes of halocarbons destroyed in the stratosphere were obtained. Those result from the time needed for their transport from the surface where they are emitted to the stratosphere where they are destroyed. Efforts should be made to update and reduce the large uncertainties on CFC lifetimes.

The environmental impact of unsaturated fluoroesters: atmospheric chemistry towards OH radicals and Cl atoms, radiative behavior and cumulative ozone creation

RSC Advances ◽  
2016 ◽  
Vol 6 (26) ◽  
pp. 21833-21843 ◽  
Author(s):  
Ana Rodríguez ◽  
Iván Bravo ◽  
Diana Rodríguez ◽  
Mercedes Tajuelo ◽  
Yolanda Diaz-de-Mera ◽  
...  
Keyword(s):  
Global Warming ◽  
Environmental Impact ◽  
Infrared Spectra ◽  
Atmospheric Chemistry ◽  
Reaction Mechanisms ◽  
Radiative Forcing ◽  
Oh Radicals ◽  
Global Warming Potentials ◽  
Cl Atoms

Atmospheric lifetimes, reaction mechanisms, infrared spectra, radiative forcing efficiencies, global warming potentials and ozone creation potentials of the allyl and vinyl trifluoroacetate were determined to assess their environmental impact.

Insights into the Zonal-Mean Response of the Hydrologic Cycle to Global Warming from a Diffusive Energy Balance Model

2018 ◽  
Vol 31 (18) ◽  
pp. 7481-7493 ◽  
Author(s):  
Nicholas Siler ◽  
Gerard H. Roe ◽  
Kyle C. Armour
Keyword(s):  
Global Warming ◽  
Energy Balance ◽  
Spatial Pattern ◽  
Radiative Forcing ◽  
Energy Transport ◽  
Hydrologic Cycle ◽  
Energy Balance Model ◽  
Balance Model ◽  
Ocean Heat Uptake ◽  
Heat Uptake

Recent studies have shown that the change in poleward energy transport under global warming is well approximated by downgradient transport of near-surface moist static energy (MSE) modulated by the spatial pattern of radiative forcing, feedbacks, and ocean heat uptake. Here we explore the implications of downgradient MSE transport for changes in the vertically integrated moisture flux and thus the zonal-mean pattern of evaporation minus precipitation ( E − P). Using a conventional energy balance model that we have modified to represent the Hadley cell, we find that downgradient MSE transport implies changes in E − P that mirror those simulated by comprehensive global climate models (GCMs), including a poleward expansion of the subtropical belt where E > P, and a poleward shift in the extratropical minimum of E − P associated with the storm tracks. The surface energy budget imposes further constraints on E and P independently: E increases almost everywhere, with relatively little spatial variability, while P must increase in the deep tropics, decrease in the subtropics, and increase in middle and high latitudes. Variations in the spatial pattern of radiative forcing, feedbacks, and ocean heat uptake across GCMs modulate these basic features, accounting for much of the model spread in the zonal-mean response of E and P to climate change. Thus, the principle of downgradient energy transport appears to provide a simple explanation for the basic structure of hydrologic cycle changes in GCM simulations of global warming.

scholarly journals Long-lived halocarbon trends and budgets from atmospheric chemistry modelling constrained with measurements in polar firn

2009 ◽  
Vol 9 (1) ◽  
pp. 991-1049 ◽  
Author(s):  
P. Martinerie ◽  
E. Nourtier-Mazauric ◽  
J.-M. Barnola ◽  
W. T. Sturges ◽  
D. R. Worton ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Radiative Forcing ◽  
Numerical Models ◽  
Atmospheric Model ◽  
Calculated Concentration ◽  
Low Concentrations ◽  
Radiative Model ◽  
Green Function Approach ◽  
Atmospheric Concentrations ◽  
Depth Concentration

Abstract. The budgets of seven halogenated gases (CFC-11, CFC-12, CFC-113, CFC-114, CFC-115, CCl4 and SF6) are studied by comparing measurements in polar firn air from two Arctic and three Antarctic sites, and simulation results of two numerical models: a 2-D atmospheric chemistry model and a 1-D firn diffusion model. The first one is used to calculate atmospheric concentrations from emission trends based on industrial inventories; the calculated concentration trends are used by the second one to produce depth concentration profiles in the firn. The 2-D atmospheric model is validated in the boundary layer by comparison with atmospheric station measurements, and vertically for CFC-12 by comparison with balloon and FTIR measurements. Firn air measurements provide constraints on historical atmospheric concentrations over the last century. Age distributions in the firn are discussed using a Green function approach. Finally, our results are used as input to a radiative model in order to evaluate the radiative forcing of our target gases. Multi-species and multi-site firn air studies allow to better constrain atmospheric trends. The low concentrations of all studied gases at the bottom of the firn, and their consistency with our model results confirm that their natural sources are insignificant. Our results indicate that the emissions, sinks and trends of CFC-11, CFC-12, CFC-113, CFC-115 and SF6 are well constrained, whereas it is not the case for CFC-114 and CCl4. Significant emission-dependent changes in the lifetimes of halocarbons destroyed in the stratosphere were obtained. Those result from the time needed for their transport from the surface where they are emitted to the stratosphere where they are destroyed. Efforts should be made to update and reduce the large uncertainties on CFC lifetimes.

Global Warming and Its Multiple Causes

2020 ◽  
Vol 3 (2) ◽  
Author(s):  
Romdhane Ben Slama
Keyword(s):  
Global Warming ◽  
Greenhouse Gases ◽  
Greenhouse Effect ◽  
Infrared Radiation ◽  
Fossil Fuels ◽  
Ambient Air ◽  
The Earth ◽  
The One ◽  
Heat Released ◽  
Emission Of Greenhouse Gases

The global warming which preoccupies humanity, is still considered to be linked to a single cause which is the emission of greenhouse gases, CO2 in particular. In this article, we try to show that, on the one hand, the greenhouse effect (the radiative imprisonment to use the scientific term) took place in conjunction with the infrared radiation emitted by the earth. The surplus of CO2 due to the combustion of fossil fuels, but also the surplus of infrared emissions from artificialized soils contribute together or each separately,  to the imbalance of the natural greenhouse effect and the trend of global warming. In addition, another actor acting directly and instantaneously on the warming of the ambient air is the heat released by fossil fuels estimated at 17415.1010 kWh / year inducing a rise in temperature of 0.122 ° C, or 12.2 ° C / century.

scholarly journals A Link between the Hiatus in Global Warming and North American Drought

2015 ◽  
Vol 28 (9) ◽  
pp. 3834-3845 ◽  
Author(s):  
Thomas L. Delworth ◽  
Fanrong Zeng ◽  
Anthony Rosati ◽  
Gabriel A. Vecchi ◽  
Andrew T. Wittenberg
Keyword(s):  
Global Warming ◽  
North America ◽  
Surface Temperature ◽  
North American ◽  
Radiative Forcing ◽  
Tropical Pacific ◽  
Global Warming Hiatus ◽  
Warming Hiatus ◽  
The Impact ◽  
The Tropical Pacific

Abstract Portions of western North America have experienced prolonged drought over the last decade. This drought has occurred at the same time as the global warming hiatus—a decadal period with little increase in global mean surface temperature. Climate models and observational analyses are used to clarify the dual role of recent tropical Pacific changes in driving both the global warming hiatus and North American drought. When observed tropical Pacific wind stress anomalies are inserted into coupled models, the simulations produce persistent negative sea surface temperature anomalies in the eastern tropical Pacific, a hiatus in global warming, and drought over North America driven by SST-induced atmospheric circulation anomalies. In the simulations herein the tropical wind anomalies account for 92% of the simulated North American drought during the recent decade, with 8% from anthropogenic radiative forcing changes. This suggests that anthropogenic radiative forcing is not the dominant driver of the current drought, unless the wind changes themselves are driven by anthropogenic radiative forcing. The anomalous tropical winds could also originate from coupled interactions in the tropical Pacific or from forcing outside the tropical Pacific. The model experiments suggest that if the tropical winds were to return to climatological conditions, then the recent tendency toward North American drought would diminish. Alternatively, if the anomalous tropical winds were to persist, then the impact on North American drought would continue; however, the impact of the enhanced Pacific easterlies on global temperature diminishes after a decade or two due to a surface reemergence of warmer water that was initially subducted into the ocean interior.

Extreme North America Winter Storm Season of 2013/14: Roles of Radiative Forcing and the Global Warming Hiatus

2015 ◽  
Vol 96 (12) ◽  
pp. S25-S28 ◽  
Author(s):  
Xiaosong Yang ◽  
G. A. Vecchi ◽  
T. L. Delworth ◽  
K. Paffendorf ◽  
L. Jia ◽  
...  
Keyword(s):  
Global Warming ◽  
North America ◽  
Radiative Forcing ◽  
Winter Storm ◽  
Global Warming Hiatus ◽  
Warming Hiatus ◽  
Extreme North
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