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Global warming is becoming a big concern for the environment since it is causing serious and often unexpected impacts on species, affecting their abundance, genetic composition, behavior and survival. So, the modeling study is necessary to investigate the effects of global warming in predator–prey dynamics. This research paper analyzed the memory effect evaluated by Caputo fractional derivative on predator–prey interaction using an exponential fear function with a Holling-type II function in the presence of global warming effect on prey and predator species. It is assumed that the densities of prey and predator species decrease due to the increase of global warming. It is considered that both prey and predator species are contributing to the increase of global warming. Also, it is considered that global warming is increasing constantly and decreasing due to the natural decay rate. All possible equilibria of the system are determined, and the stability of the system around all equilibria points is investigated. Around the interior equilibrium point, the Hopf bifurcation is also theoretically and numerically studied. A number of numerical simulation results are presented to demonstrate the impacts of fear, fractional order and global warming on the behavior of the model. It is observed that the global warming effect on predator species may destabilize the system but ultimately the system may become stable. Again, it is obtained that the natural decay rate of global warming can stabilize the system initially but a higher decay rate may destabilized the system. It is also found that the fractional-order model is determined to be more stable than the integer-order model.

We can limit the future temperature impact of climate change in two ways: (i) reducing our use of CO2 emitting fuels as an energy source (abatement), and (ii) using negative emission technologies (NETs) to remove existing CO2 from the atmosphere (removal). Using a modification of the DICE model, we analyze the optimal use of these two policy responses to climate change. After calibrating the marginal costs of abatement and CO2 removal to the latest scientific information, we find that carbon removal must play a very large role in an optimal policy. If this policy is followed, we find that the Paris-Agreement 1.5–2^∘C warming by 2100 target is not just aspirational, but optimal. When an important role is played by NETs to control global warming, the decrease in carbon emissions can be more gradual, reducing transition risk and social dislocations. We examine the impact on the economy of large-scale carbon removal programs, the potential for moral hazard and the logistical problems associated with the storage of the removed carbon.

The effect of income and extreme temperatures on the residential electricity consumption in Spain is analyzed. An electricity demand function is estimated by means of ordinary least squares-Driscoll and Kraay, feasible generalized least squares, and quantiles panel data techniques, for the total of the sample, and by coastal climatic zones. The results support the energy-environmental Kuznets curve hypothesis for Spain, the continental, and Mediterranean zones. An N form is found for the Atlantic zone. The results also reflect that increases in temperature above 22^∘C and decreases below 15^∘C increase electricity consumption, this increase being progressive as temperatures vary. Thus, extreme temperature generates electricity consumption growth. The Mediterranean zone is most sensitive to these temperature changes. The results also show that electricity consumption is more sensitive to cold than to heat. The results suggest an inefficient use of heating and cooling appliances in the areas with the highest electricity consumption.

Climatic monitoring shows that 2015 has been the warmest year around the globe since the first modern observation was conducted in1880. Asia has witnessed its average land surface temperature reaching the highest level since 1901; China has seen the warmest year since 1951 when it had completed the meteorological records; the CO₂ concentration in the atmosphere exceeds 400ppm; the ocean thermal capacity sets a new record high; and the global sea surface temperature has also been the highest since 1870. Against the backdrop of global warming, the incidence of strong El Niño and the duration of El Niño in the central and eastern equatorial Pacific Ocean have both significantly increased, while the time interval between El Niño and La Niña has shortened. The 2015/16 “Super” El Niño event exceeds previous two “Super” El Niño events in several indexes (e.g. durative event and peak intensity), although the 1982/83 El Niño event keeps the record in terms of the intensity of atmospheric response to the ocean. Influenced by the 2015/16 “Super” El Niño event, the general atmospheric circulation was significantly abnormal with extreme climate events frequently occurring in many places worldwide.

We studied the relevance of the secular variation of Japanese interest in energy and environmental problems to the information primarily released by the news media. From the investigation of the extent of public interest in three matters, the global warming, the energy saving and nature, all indicated by opinion surveys, the number of newspaper articles and the frequency of Internet retrieval search, we proposed a model such that the public interest along with the acquired public knowledge were given as a function of public memory of the information primarily provided by the news media. The society was assumed here to be immersed in a virtual field of information environment, which induced the collective interest of the public and was proportional in strength to the extent of the public memory with oblivion. Introducing two types of oblivion function, we found the model to well reproduce the real time-variation of the Japanese interest, except for the case of nature, almost irrespective to the form of the function. Some comments were made on the attenuation of the public interest that occurred when the field became weakened.

Global warming is a rising problem caused by humans. As we release greenhouse gases into the atmosphere, we are rapidly heating our planet. Thankfully, there are solutions, such as reforesting, using clouds to protect the Earth from the sun’s rays, and switching from fossil fuels to renewable energy sources that don’t release greenhouse gases. Working together, we can limit the effects of global warming.

Current human-induced climate change arises primarily from the heating of the planet mainly from changes in atmospheric composition, and temperature change is one manifestation. The increasing greenhouse gases, notably carbon dioxide from burning fossil fuels, lead to Earth’s Energy Imbalance (EEI), altering the flow of energy through the climate system, and the dissemination of excess energy is partly what determines how climate change is manifested. Some of the extremes being experienced, especially those involving drought, convection, storms, flooding, and the water cycle, are mostly driven by aspects of heating and, while temperature contributes through the water-holding capacity of the atmosphere, it is more a consequence than a cause. Afterall, water is the air conditioner of the planet. The United Nations, and especially the Intergovernmental Panel on Climate Change (IPCC) in their Summary for Policy Makers, focus on global temperature targets rather than broader facets of climate change including EEI, and do not always adequately discriminate between temperature and heating. This also has consequences for future climate if or when heating is brought under control by cutting emissions. Improvements are needed in expressing how the climate is changing by properly accounting for the flow of energy through the climate system.

Written in 1992, this study examined the economic cost of reducing emissions of carbon dioxide and other greenhouse gases in comparison to the economic benefit of avoiding future damage from global warming. It made estimates of damage to the US economy for several categories, especially agriculture, forest loss, sea-level rise, electricity for air-conditioning, water supply, urban pollution, species loss, and loss of human life. It introduced a focus on a horizon of 300 years, when deep-ocean absorption would begin to reduce atmospheric concentrations once again. This horizon was far longer, and involved far greater warming, than the usual benchmark (a doubling of carbon dioxide concentration, expected to occur by 2025). On the abatement cost side, it used estimates by leading energy-economic models of the cost of replacing fossil fuels (especially coal) with alternative energy sources. It also considered lower-cost measures curbing deforestation (which emits carbon dioxide) and planting new forested area (which absorbs it). The study gave special attention to the correct “social discount rate” to apply when examining such long-term effects. It found that after consideration of risk, economic benefit-cost analysis justified a reduction by one-third in global emissions from their 1990 level, to a plateau that by 2100 would represent a cutback of 80% from the level of emissions otherwise reached.

As the global mean sea surface temperature (SST) increases, the frequency and intensity of marine heatwaves (MHWs) are also increasing. A model evaluation is needed to better understand future projections for MHWs. In this study, we evaluated MHWs in a historical simulation of 14 CMIP6 (Coupled Model Project Intercomparison Phase 6) models in the North Pacific Ocean (NPO) where MHW occurs frequently by comparing the OISST (Optimum Interpolation Sea Surface Temperature) reanalysis data for 33 years (1982∼2014). The CMIP6 models overestimated the annual mean cumulative duration of MHWs in the NPO by approximately 25 days compared to the OISST while the frequency was underestimated by 0.3∼0.6 events per year. Over 80% of CMIP6 models underestimated the spatial mean of the mean and maximum intensities, although a majority (60%) of the models overestimated the intensity north of the Kuroshio extension region, presumably by Kuroshio overshooting. Furthermore, because the CMIP6 multi-model ensemble underestimated the increasing trend regarding MHW characteristics (duration, frequency, and intensity) according to warming, it is necessary to investigate the influences of trend underestimation in the characteristics of MHWs on future changes in MHWs. Our results suggest that the MHW biases are still significant in CMIP6 models, demanding an increase in model horizontal resolution.