Latest IPCC Report Research Articles

Predicting willingness to pay and implement different rooftop strategies to characterize social perception of climate change mitigation and adaptation

With the latest IPCC report, dramatic global climate action must be taken immediately to limit global warming to 1.5 °C, or face more frequent and extreme weather events with catastrophic implications. Cities must invest in climate resilience development; however, government policies are only effective if they are supported by the society in which they serve. As such, this study aims to characterize the social perception of climate resilience development, in particular the implementation of sustainable urban rooftop strategies, to support policy makers and enable individual action. This was accomplished through the analysis of 1,100 answered surveys in Cerdanyola del Vallès (Spain), to assess one’s willingness to pay (WTP) and willingness to implement (WTI) rooftop strategies according to: 1. socio-demographical characteristics; 2. social perceptions and beliefs; and 3. surrounding land use and land cover, and vulnerabilities identified through temperature and normalized difference vegetation index (NDVI) maps. The results of this study found age played a significant role in predictability, with 18–39-year-olds being the most willing to pay and implement the various rooftop scenarios. However, our results uncovered societal inequality as those 85+ were the second group most interested in rooftop agriculture but the most financially restricted. Belief in the viability of rooftop strategies increased respondents WTP and WTI while having access to ones’ rooftop increased willingness to partake in rooftop food cultivation and enhance rooftop greenery. A new finding presented by this study is the quantifiable impact that urban greenery plays on increasing survey respondents WTP and WTI.

Prospects

The latest IPCC report which is named ‘The Synthesis Report , Climate Change 2023’ was released on 20 March 2023 to inform the 2023 Global Stocktake under the United Nations Framework Convention on Climate Change. The report finds that ‘there is more than 50% chance that global temperature rise will reach or surpass 1.5 degrees Celsius between 2021 and 2040 across studied scenarios, and under a high-emissions pathway, specifically, the world may hit this threshold even sooner, between 2018 and 2037.’ These findings again emphasise the growing pressures and challenges that deltas are confronting in their path towards future development. It is evident that the global imperative for deltas to adapt has reached an unprecedented level, but at the same time the question arises if adaptation is enough. Especially considering the scope of societal challenges that need to be the point of departure for sustainable spatial transformation in general. Aren't they of such a fundamental nature that we need to reconsider our urban system as a whole and aim for transformation instead of adaptation? Looking more closely to the societal challenges we can organise them according to their environmental and socio-economic drivers. The environmental drivers are the climate crisis and the biodiversity crisis. The socio-economic drivers are ongoing urbanisation, the energy transition, and the new economy.

Does a change in the ‘global net zero’ language matter?

Non-technical summary Changes in language used in long term climate policy can undermine their credibility and discourage climate action. Previous IPCC reports have promoted an idea of reaching ‘global net zero’ (GNZ) emissions by 2050 in order to limit global warming to 1.5 °C. In the latest IPCC Report, this language has been changed. To understand the impact of this change, we survey COP 26 participants to test their willingness to accept a shift in long term policy goals. We find a low tolerance for a change and, indeed, there is substantial finance, business and political effort behind the idea of reaching GNZ by 2050. This suggests that GNZ by 2050 will remain central to climate action. Technical summary Consistency in language in long term policy goals is central to building a (political) constituency in support of the Paris Agreement. Changes in language can undermine policy credibility, and stall effective mitigation action. Recent changes in IPCC language to describe ‘global net zero’ (GNZ) as being reached in the ‘early or mid 2050s’ (AR6 WG1) could risk undermining the substantial cultural, political and financial momentum that has developed behind the interpretation – first developed by the IPCC SR 1.5 °C Report – that GNZ must be reached by 2050. We survey COP 26 participants to test their willingness to accept a shift in policy goals and find a strong preference for a ‘stable’ long term policy target, widely interpreted as reaching ‘GNZ by 2050’, and a rejection of flexibility in long term policy targets, even as new scientific information becomes available. ‘GNZ by 2050’ is no longer a science based target, but has transitioned to a cultural and political metaphor actively used by stakeholders to guide their climate decision making. This makes ‘GNZ by 2050’ no less valid than the original scientific concept. This may stimulate further ‘political calibration’ or between the policy and modelling communities. Social media summary Sig. momentum is behind global net zero by 2050.Will changes in IPCC mitigation language de-rail global climate action?

PROCEDURE OF EXTRACTING THIN ICE AREAS IN THE SEA OF OKHOTSK USING MODIS DATA

Abstract. The latest IPCC report clearly stated that the human influence is the main reason of sea ice reduction in the Arctic. Importance of sea ice monitoring from space is increasing. In addition, the heat flux of ice in thin ice areas is strongly affected by the ice thickness difference. Therefore, ice thickness is one of the important parameters of sea ice. The authors have been studying on extracting thin ice areas using optical sensor such as MODIS for years. In this paper, the authors summarized the procedure of our study starting from comparing in-situ measurement of ice thickness with high resolution optical sensor RSI data, and finally developing the thin ice area extraction algorithm using MODIS. Estimating ice thickness from optical sensor data is not easy. However, through our study, the authors have verified the possibility of extracting thin ice areas using optical sensor data observed from satellites. In this study, the authors define “thin ice areas” as ice which thickness is less than about 30 cm with reflectance much lower than thick ice. The basic idea of the algorithm is to use the scatterplots of MODIS band 1 & 2 reflectance and extract thin ice areas using the distribution difference of thin ice against water, thick ice, clouds. Not all but most of the thin ice areas could be extracted using the algorithm.

Ocean Acidification in the Arctic in a Multi-Regulatory, Climate Justice Perspective

The latest IPCC report on Ocean and Cryosphere in a Changing Climate, which builds upon previous IPCC's reports, established a causal link between anthropogenic impacts and ocean acidification, by noting a significant decrease in the Ocean's uptake of CO2, with consequent damage to Earth's ecosystems, which in turn has traceable repercussions on the Arctic Ocean and then from the Arctic to the Planet Earth. The impact of ocean acidification is not only in the biological ecosystem but also on human activities, such as livelihood, food security, socio-economic security and developing communities. However, who can possibly be held ethically/legally responsible for ocean acidification from a climate justice perspective? Since what happens in the Arctic does not stay there, a more systematic law and policy approach to study options and responses in a multi-level, climate- ethical, global perceptive is needed. This paper sheds light on the legal responses available at global, regional and national levels to ocean acidification in a law of the sea and ocean context, both in the Arctic and from the Arctic. The gaps in legal and policy responses in connection to the ethical climate component will be identified. It will shed light on the planetary limits that humanity needs to stay within in order to maintain the future of the Earth. Since it touches upon questions of legal responsibility, on who is responsible for ocean acidification, it will connect to the “supply side” of fossil fuels production and global extraction projects causing anthropogenic CO2emissions, one of the major causes of ocean acidification. It will also identify which actors, be they “officials” or “non-officials” (such as international organizations, states, regional institutes, Arctic citizens or evenforums) should be held ethically responsible, and who should take action.

Constraints on global oceanic emissions of N<sub>2</sub>O from observations and models

Abstract. We estimate the global ocean N2O flux to the atmosphere and its confidence interval using a statistical method based on model perturbation simulations and their fit to a database of ΔpN2O (n = 6136). We evaluate two submodels of N2O production. The first submodel splits N2O production into oxic and hypoxic pathways following previous publications. The second submodel explicitly represents the redox transformations of N that lead to N2O production (nitrification and hypoxic denitrification) and N2O consumption (suboxic denitrification), and is presented here for the first time. We perturb both submodels by modifying the key parameters of the N2O cycling pathways (nitrification rates; NH4+ uptake; N2O yields under oxic, hypoxic and suboxic conditions) and determine a set of optimal model parameters by minimisation of a cost function against four databases of N cycle observations. Our estimate of the global oceanic N2O flux resulting from this cost function minimisation derived from observed and model ΔpN2O concentrations is 2.4 ± 0.8 and 2.5 ± 0.8 Tg N yr−1 for the two N2O submodels. These estimates suggest that the currently available observational data of surface ΔpN2O constrain the global N2O flux to a narrower range relative to the large range of results presented in the latest IPCC report.

Renewable Energy in Central America: One Step Forward, One Step Back, and Another Tentative Step Forward Again

We are at an historical crossroads. The latest IPCC report gives dire predictions about potential losses from climate change, ranging from high sea levels to deterioration of agricultural production. Although emissions are still concentrated in the North, the most‐rapid growth of emissions is occurring in the South, suggesting the need for major changes in the trajectory of its economic development. Massive aid flows for climate‐change mitigation and adaptation lack any clear framework. We begin the task by examining the evolution of Central American electricity systems, seeking to explain the exceptional ability of several countries wracked by conflict, weak institutions, and struggling economies to move toward renewable fuels. We use first‐person interviews, government documents and websites, and consultant and expert reports to examine the largely unrecognized achievements. The necessity of finding alternative energy is not in question, but how these countries overcame the financial, technical, and policy challenges should be of great interest and could potentially provide valuable lessons for other countries.

Uncertainty discourses in the context of climate change: A corpus-assisted analysis of UK national newspaper articles

AbstractUncertainty is intrinsic to science, to knowledge acquisition and risk assessment. When communicating about climate change, however, uncertainty can be used and understood as ‘not knowing’, that is, as ignorance. In this article we aim to understand how ‘uncertainty’ is used in a specific cultural and media context at two important periods in time. Using a corpus linguistic approach, we examine how ‘uncertainty’ was used in the context of UK press coverage of climate change in 2010 (following ‘Climategate’) and in 2014−15, after the latest IPCC report had been published. We find that after Climategate and the (failed) Copenhagen summit, ‘uncertainty’ was used to question the authority and credibility of climate science; after the latest IPCC report and in the run-up to the (more successful) Paris summit, discussions focused on uncertainties inherent in various climate change mitigation activities and associated with the economy, environment and politics more generally.

Effect of a high-end CO2-emission scenario on hydrology

In the latest IPCC report, worst case scenarios of climate change describe average global surface warming of up to 6°C from pre-industrial times by the year 2100. This study high- lights the influence of a high-end 6 degree climate change on the hydrology of a catchment in central Denmark. A simulation from the global climate model, EC-Earth, is downscaled using the regional climate model HIRHAM5. A simple bias correction is applied for daily reference evapo- transpiration and temperature, while distribution-based scaling is used for daily precipitation data. Both the 6 degree emission scenario and the less extreme RCP4.5 emission scenario are eval- uated for the future period 2071−2099. The downscaled climate variables are applied to a fully dis- tributed, physically based, coupled surface−subsurface hydrological model based on the MIKE SHE model code. The impacts on soil moisture dynamics and evapotranspiration show increasing drying-out tendencies for the future, most pronounced in the 6 degree scenario. Stream discharge and groundwater levels also show increased drying due to higher evapotranspiration. By compar- ing the 6 degree scenario with other emission scenarios, it is found that the most prominent changes in the water balance are caused by drying out of soils rather than precipitation effects.

The Variability of Seasonal and Annual Extreme Temperature Trends of the Latest Three Decades in Romania

Abstract In the latest IPCC report (2014) it was estimated that since the mid-20th century, the number of cold days and nights has decreased and the number of warm days and nights has increased in large parts of Europe. Some recent analyses have found that mean summer maximum temperature change over Europe was +1.6 ± 0.4 °C during 1880 to 2005. It seems that human influence has contributed to the observed global scale changes in the frequency and intensity of daily temperature extreme. The objective of this work was to identify spatial variations of the seasonal and annual extreme temperature variability and trends over Romania in the period 1985-2014. Starting with a large climatological database (30 years of daily data for 29 locations from Romania), daily minimum, maximum and amplitude temperature data were condensed into normal probability functions for which the assumption of normal distribution was accepted by the Shapiro-Wilk statistical test. These functions were then used to calculate the appearance probability of annual and monthly temperatures values. Temperatures which appear with different probabilities all year long were computed with “NORMDIST” function from Microsoft Office Excel. Based on these values data thematic maps were generated with isolines drawn by geo-statistical interpolation (kriging method of Surfer®, Golden Software, 2012). Comparing the increasing trend per decade expressed by probabilities, we found that the minimum temperature had almost the same rate (21.6% in a decade) as the maximum ones (21.0% in a decade) and mean daily temperature amplitude remained unchanged from 1985 to 2014. We identified the presence of an increased variability of annual mean temperature trends between the different climatological stations. It was noted that the level of statistical significance of maximum and minimum temperature linear trends per decade was low during winter, spring and autumn. But this level of significance was very high for June, July and August months.

Latest IPCC report confirms global warming—and human influence

Latest IPCC report confirms global warming—and human influence

Anthropogenic contribution to cloud condensation nuclei and the first aerosol indirect climate effect

Atmospheric particles influence the climate indirectly by acting as cloud condensation nuclei (CCN). The first aerosol indirect radiative forcing (FAIRF) constitutes the largest uncertainty among the radiative forcings quantified by the latest IPCC report (IPCC2007) and is a major source of uncertainty in predicting climate change. Here, we investigate the anthropogenic contribution to CCN and associated FAIRF using a state-of-the-art global chemical transport and aerosol model (GEOS-Chem/APM) that contains a number of advanced features (including sectional particle microphysics, online comprehensive chemistry, consideration of all major aerosol species, online aerosol–cloud–radiation calculation, and usage of more accurate assimilated meteorology). The model captures the absolute values and spatial distributions of CCN concentrations measured in situ around the globe. We show that anthropogenic emissions increase the global mean CCN in the lower troposphere by ∼60–80% and cloud droplet number concentration by ∼40%. The global mean FAIRF based on GEOS-Chem/APM is −0.75 W m−2, close to the median values of both IPCC2007 and post-IPCC2007 studies. To the best of our knowledge, this is the first time that a global sectional aerosol model with full online chemistry and considering all major aerosol species (including nitrate, ammonium, and second organic aerosols) has been used used to calculate FAIRF.

Anthropogenic influence on SOA and the resulting radiative forcing

Abstract. The effect of chemical changes in the atmosphere since the pre-industrial period on the distributions and burdens of Secondary Organic Aerosol (SOA) has been calculated using the off-line aerosol chemistry transport model Oslo CTM2. The production of SOA was found to have increased from about 35 Tg yr−1 to 53 Tg yr−1 since pre-industrial times, leading to an increase in the global annual mean SOA burden from 0.33 Tg to 0.50 Tg, or about 51%. The effect of allowing semi-volatile species to partition to sulphate aerosol was also tested, leading to an increase in SOA production from about 43 Tg yr−1 to 69 Tg yr−1 since pre-industrial times, while the annual mean SOA burden increased from 0.44 Tg to 0.70 Tg, or about 59%. The increases were greatest over industrialised areas, especially when partitioning to sulphate aerosol was allowed, as well as over regions with high biogenic precursor emissions. The contribution of emissions from different sources to the larger SOA burdens has been calculated. The results suggest that the majority of the increase was caused by emissions of primary organic aerosols (POA), from fossil fuel and bio fuel combustion. As yet, very few radiative forcing estimates of SOA exist, and no such estimates were provided in the latest IPCC report. In this study, we found that the change in SOA burden caused a radiative forcing (defined here as the difference between the pre-industrial and the present day run) of −0.09 W m−2, when SOA was allowed to partition to both organic and sulphate aerosols, and −0.06 W m−2 when only partitioning to organic aerosols was assumed. Therefore, the radiative forcing of SOA was found to be stronger than the best estimate for POA in the latest IPCC assessment.

A handful of carbon

Locking carbon up in soil makes more sense than storing it in plants and trees that eventually decompose, argues Johannes Lehmann. Can this idea work on a large scale? With the rash of IPCC reports in climate much in the news, geoengineering — the deliberate large-scale modification of the environment — is now being taken seriously in scientific and political circles that would previously have scoffed at the notion. Oliver Morton reports on the state of play in the field [News Feature p. 132] On the climate change mitigation front, the incorporation of ‘biochar’ into the soil is one idea gaining support. Johannes Lehmann argues that trapping biomass carbon in this way is more effective than storing it in plants and trees that will one day decompose. The latest IPCC report — round 3 — is covered in the News pages this week.

Climate panel offers grounds for optimism

The cost of fighting global warming may not be as high as feared. With the rash of IPCC reports in climate much in the news, geoengineering — the deliberate large-scale modification of the environment — is now being taken seriously in scientific and political circles that would previously have scoffed at the notion. Oliver Morton reports on the state of play in the field [News Feature p. 132] On the climate change mitigation front, the incorporation of ‘biochar’ into the soil is one idea gaining support. Johannes Lehmann argues that trapping biomass carbon in this way is more effective than storing it in plants and trees that will one day decompose. The latest IPCC report — round 3 — is covered in the News pages this week.