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A search for human influences on the thermal structure of the atmosphere
Abstract
Several recent studies have compared observed changes in near-surface temperature with patterns of temperature change predicted by climate models in response to combined forcing by carbon dioxide and anthropogenic sulphate aerosols. These results suggest that a combined carbon dioxide + sulphate aerosol signal is easier to identify in the observations than a pattern of temperature change due to carbon dioxide alone. This work compares modelled and observed patterns of vertical temperature change in the atmosphere. Results show that the observed and model-predicted changes in the mid- to low troposphere are in better accord with greenhouse warming predictions when the likely effects of anthropogenic sulphate aerosols and stratospheric ozone reduction are incorporated in model calculations, and that the level of agreement increases with time. This improved correspondence is primarily due to hemispheric-scale temperature contrasts. If current model-based estimates of natural internal variability are realistic, it is likely that the level of time-increasing similarity between modelled and predicted patterns of vertical temperature change is partially due to human activities.
... Climate change is undoubtedly the most critical issue confronting humanity in this century. It is a problem driven by human activities [52] and gives rise to severe crises, including extreme temperatures exceeding 49 • C (120 • F) [37] and devastating floods with up to 150 mm of rainfall within a span of 15 hours [13]. In response to these challenges, certain businesses are taking proactive measures to address environmental concerns. ...
... Lelieveld et al. (2015) postulated that by the year 2050, the premature mortality deaths caused by the outdoor PM 2.5 would be around 6.2 million annually with an estimated present-day death of 3.15 million deaths annually. Human activities increase the carbon dioxide in the atmosphere by 30%, because of the radiative forces (Santer et al. 1995). Even research by Liu and Rodriguez, 2005 stated that the average global temperature was found to be increased by 2.15-3.4 ...
The recent heavy downpours in specific regions have initiated several studies on the relationship between aerosol and precipitation. The increase in pollution/population and the recent outbreak of diseases and environmental deterioration have been preceded by an increase in aerosol concentration, which would be directly related to precipitation. Considering this background, several studies are being conducted to define a clear relationship between aerosol concentration and precipitation. With the current need to understand aerosol and its characteristics to reduce pollution, research in this domain has significantly increased followed by the demand for control measures and impacts on human health and the environment. A systematic literature review is followed to aid future researchers in mapping the studies and themes related to aerosol and precipitation. Some studies have shown the direct effect of aerosols on the reduction in land surface temperature, by reflection and indirectly enhancing the cloud reflectivity. Even though the research studies conducted in the past have not achieved the perfect correlation of airborne particles and their influence on precipitation around the globe. Our study attempts to show the bibliometric literature review of aerosol and precipitation studies. The mapping stated four conceptual structures of different theme domains: Sampling and retrieval methods, Characterization and effects, Assessment studies, Health and environmental impacts, and Modeling and measures. Lastly, the mapping identified the limitations of the research review, and the scope of future studies to be carried out.
... The decomposed air temperature (Fig. 7c) also suggests that the ZW3 pattern prevails the other harmonics near the 60°N latitude, in accordance with the zonal fluctuations found in upper-level geopotential heights. In order to quantitatively evaluate the consistency between the modeled and observed patterns, we employ the spatial pattern correlation method, which has been used in previous studies to compare the modeled and observed results (AchutaRao; Sperber 2006; Santer et al. 1996). The As suggested from observational analysis, the SAT is closely related to the upper-level atmospheric circulation. ...
The Northern Hemisphere warms faster under global warming and suffers from more frequent heatwaves, causing considerable social and economic damage. The Northern Hemisphere surface warming exhibits strong regionality, with multiple “hotspots” (enhanced warming), but the relations among them remain unclear. This study finds a dominating zonal wavenumber-3 (ZW3) trend pattern in the upper-level geopotential heights during the boreal summer. The summer geopotential heights show significant increasing trends along the latitudinal circle around 60°N, with three centers located over northeastern America, western Eurasia, and eastern Siberia. The regionally enhanced surface warming trends are closely linked to the increased geopotential through the reduced cloud cover, exhibiting a consistent ZW3 pattern. The model simulations forced by sea surface temperature (SST) and Arctic sea ice (SIC) indicate that the SST forcing plays an important role in generating the ZW3 pattern, while the contribution of the SIC is minimal. A theoretical barotropic model can fairly reproduce the observed ZW3 structure forced by a heating source located over the subtropical North Atlantic, where the SSTs show prominent warming trends and a close relationship with the ZW3 pattern. Our results indicate that the “hotspots” may be interconnected and are related to a Rossby wave train with a ZW3 structure. It highlights a vital role of tropical/subtropical SSTs on the atmospheric circulation and the associated surface enhanced warming over the mid-high latitudes, which may have great implications in the coordinated heatwave events and tropical-extratropical teleconnections.
... Detection and attribution approaches provide a substantial advance by connecting societal impacts to ongoing climate change and rigorously quantifying the role of human forcing of the climate in trends of impacts (18). Detection and attribution approaches aim to statistically detect whether a variable/impact is changing and attribute how much of the observed change was contributed by anthropogenic climate change (19)(20)(21). ...
Significance
Human-caused climate change could impact respiratory health, including asthma and allergies, through temperature-driven increases in airborne pollen, but the long-term continental pollen trends and role of climate change in pollen patterns are not well-understood. We measure pollen trends across North America from 1990 to 2018 and find increases in pollen concentrations and longer pollen seasons. We use an ensemble of climate models to test the role of climate change and find that it is the dominant driver of changes in pollen season length and a significant contributor to increasing pollen concentrations. Our results indicate that human-caused climate change has already worsened North American pollen seasons, and climate-driven pollen trends are likely to further exacerbate respiratory health impacts in coming decades.
... 1,2 The temperature of the planet is rising, and the pace of climate change is accelerating. [3][4][5][6][7][8] There has been an increase in atmospheric carbon dioxide (CO 2 ) of nearly 50% since 1990, and the last decade was the warmest decade ever recorded. 9 Higher temperatures are associated with lower agricultural crop yields, affecting nutrition, food, and water security 3 and may also worsen growth faltering in malnourished children. ...
We calculated carbon emissions associated with air travel of 4,834 participants at the 2019 annual conference of the American Society of Tropical Medicine and Hygiene (ASTMH). Together, participants traveled a total of 27.7 million miles or 44.6 million kilometers. This equates to 58 return trips to the moon. Estimated carbon dioxide equivalent (CO2e) emissions were 8,646 metric tons or the total weekly carbon footprint of approximately 9,366 average American households. These emissions contribute to climate change and thus may exacerbate many of the global diseases that conference attendees seek to combat. Options to reduce conference travel–associated emissions include 1) alternating in-person and online conferences, 2) offering a hybrid in-person/online conference, and 3) decentralizing the conference with multiple conference venues. Decentralized ASTMH conferences may allow for up to 64% reduction in travel distance and 58% reduction in CO2e emissions. Given the urgency of the climate crisis and the clear association between global warming and global health, ways to reduce carbon emissions should be considered. Copyright © 2020 by The American Society of Tropical Medicine and Hygiene
Climate change has become an issue of great concern all over the world. The Globe is getting warmer day by day which has alerted the people living in it. The earth is getting dirty, creating difficulties for the human beings as well as the other living creatures on earth. It has been realized that the world will become a dangerous place to live if measures are not taken to reduce or control the hazardous components in water and air. The issue has got tremendous attention from the developed world, and many summits and conferences have been held to discuss the factors for climate change and increasing pollution in the whole world. Many measures have been suggested and many of them have been practiced but there is no significant positive change in the sensitivity of the challenge ahead. The purpose of this article is to analyze the current situation and factors for the climate change worldwide. The sensitivity of the issue in Pakistan will also be evaluated while possibilities and options will be elaborated to face the challenges ahead. Introduction Climate change is one of the greatest challenges and issues of today's world in which we all are living. But at the same time today's world is driven by media. From North to South and from East to West, the whole earth is facing the problem of Climate change with its effects on economy, public health, social relations, politics and other spheres of life. Developed as well as the developing world is facing almost the same threats from the climate change. The world is getting warmer and warmer, year by year. The sea level is increasing year by year. Thousands of species of animals living in water and lands are being diminished every year because of the global warming.
This article discusses the comprehensive knowledge-based prediction of the second COVID-19 wave particularly in India and its associated possible reasons, consequences, and suggestions. The knowledge-based prediction was released dated 21 March 2021 and it been stated that the ongoing COVID-19 wave (second) going to be much larger and faster than the first if ethical testing campaign, tracing and isolation (hereafter TTI) followed by COVID-19 protocols based on scientific facts are not respected effectively and timely. Some of the possible reasons for the predicted COVID-19 surge were linked to the following the delay and unsustainability in large-scale and large number vaccine drive, lack of supremacy in strategy, design, planning and swift execution in conducting ethical TTI, lack of insight and planning (from small to large scale) to handle the COVID-19, no lesson learned from the first wave spread, intervention in the chain breaking by opting random testing etc. These purported to give enough time to spread and the mutations. Scientifically, such a disaster could have been avoided with an effective timely planned ethical TTI approach. Because the facts based on science, say that COVID-19 has a ~14-day cycle between the infection and recovery. If any country makes use of this duration in (for example -21 days or ~ 500 hrs.) effectively and timely in ethical TTI, only in a shorter time frame, the country can break the chain-of-infection and possibly get rid of it shortly. If not, then it may results in a prolonged crisis leading to a huge social, economic and fatality. In the line, the present article discusses prediction done, all likely reasons, consequences, and suggestions associated with the COVID-19 surge.
You may also find this article in the "World Health Organization (WHO)" COVID-19 Global literature on coronavirus disease
https://pesquisa.bvsalud.org/global-literature-on-novel-coronavirus-2019-ncov/resource/pt/covidwho-1473102
Improving environmental sustainability in the IR suite has been enlightening, enriching and rewarding. By reducing, reusing and recycling, we not only save money, we can be leaders in the green healthcare revolution.