Volume 12 Issue 12, December 2022

Many natural disaster insurance markets were designed under historical distributions of climate risk that differ from those prevailing today. These differences create challenges for natural disaster insurance markets to mitigate the effects of climate change and also increase demand for innovative policy solutions.

For effective climate policy, we need both classic and behavioural policies. Green nudges facilitate the effectiveness of a carbon tax by increasing the salience of the tax, harnessing pro-climate concerns, extending the reach of a tax by targeting behaviours directly and, importantly, increasing public acceptance of carbon taxes.

As regulatory attention on scope 3 emissions mounts, the ‘double-counting’ concern cited by companies can be addressed by allocating shared responsibility across the supply chain. Measurement and data collection present more substantial challenges in reaching an effective allocation.

The 27th Conference of the Parties (COP27) is being held in November 2022 in Sharm el-Sheikh, Egypt. Having a climate summit hosted in an African country makes it timely to highlight climate change research from the continent. We asked a selection of researchers to share their thoughts on current research questions and how they affect African responses to climate change.

Corporate funding for academia often causes unease about the independence and integrity of such research. Now, a study shows that academia partnerships with the energy sector are more favourably inclined towards fossil fuels than to renewables.

Under climate change, the mountain snowpack worldwide is being reduced. Now, research warns of a likely transition to low-to-no snowpack in the American Cordillera, with consequences for freshwater availability.

A lack of observed increases in flooding with climate change has been difficult to explain. Now, research shows a decline in snowmelt to be the cause.

Increasing climate ambition through 2030 will be crucial to limiting global peak temperature changes this century. Countries need to ratchet their 2030 pledges made in Glasgow to reduce temperature overshoot and consequently reduce the risks of irreversible and adverse consequences to natural and human systems.

Analysis of tweets relating to the Conference of the Parties (COP) climate summits reveals greater polarization during COP26 than during previous summits. This increase in polarization is associated with growing right-wing engagement and emerged following the global climate strikes in 2019. Surprisingly, one topic unites pro-climate and climate-sceptic groups — ‘political hypocrisy’ — accusations of which have increased since 2019.

Investigating the unprecedented 2021 heatwave in the North American Pacific Northwest revealed that a complex interaction between atmospheric dynamics, soil moisture and temperature nonlinearly amplified the event beyond a five-sigma anomaly. These findings may contribute to a better understanding of the physical drivers of future heat extremes.

A meta-analysis reveals greater variation in heat tolerance within marine than terrestrial taxa. This variation corresponds to the spatial patterns in the maximum temperature populations of marine species experience. Although populations at the equatorward range edges of species’ distributions are particularly vulnerable to warming, standing genetic variation within species might promote an adaptive response elsewhere.

In this Perspective, the authors argue that radical, rather than conventional, interventions are necessary to address climate change. They discuss the definitions and interpretations of the term ‘radical’, and present a typology of radical intervention that addresses the root drivers of climate change.

The adoption of some climate policies can facilitate the subsequent adoption of other policies, which is referred to as policy sequencing. Across sectors and countries, policy sequences often play an important role in the adoption and stringency of carbon pricing.

The degree to which aerosols influence surface temperatures is not well understood. Here, the authors argue that reducing the uncertainties in the climate response to aerosol forcing is one of the key challenges to reduce overall uncertainties of warming projections.

Polarization and the resulting political deadlock have become key barriers to more ambitious climate action. Using Twitter data between Conferences of the Parties, this research identifies a trend of increasing polarization driven by growing right-wing activity alongside accusations of political hypocrisy.

University-based energy centres play an important role in climate discourse but many are funded by fossil fuel businesses. This study shows that fossil-fuel-funded centres express more positive sentiment towards natural gas, compared to renewable energy, than those not funded by the fossil industry.

Many countries have submitted updated and new emissions reduction pledges in COP26, but further ratcheting of pledges is needed to reach the 1.5 °C goal. Ratcheting near-term ambition through 2030 could bring the largest climate benefits and avoid potential long-term temperature overshoot.

Accurately assessing emissions reductions for various greenhouse gases to stay within temperature targets is important. Here, an adaptive approach, based solely on observations and not on model projections, allows quantification of emissions reductions required to achieve any temperature target.

The North American Pacific Northwest experienced an unprecedented heatwave in summer 2021. This study shows that atmospheric circulation features and regional soil dryness both amplified the event’s severity; future warming increases the chance of an equivalent or stronger event.

Future changes and regional differences in snowpacks are unclear. Here the American Cordillera mountain range, spanning the Americas, is estimated to lose snow faster in the southern midlatitudes—global warming should be limited to below 2.5 °C to prevent low-to-no-snow conditions across the range.

Climate change is expected to intensify the hydrological cycle, but how this translates into changes in river floods is not clear. Here, the authors show that changes in river flood discharge differ between flood types, with increases in rainfall-induced floods and decreases in snow-related floods.

The authors analyse the impacts of drought on tree growth for various species of various ages to assess the influences of forest demographic shift on future drought responses. The increasing proportion of young trees showing greater growth reduction to drought raises concern on future carbon storage.

The authors quantify the thermal tolerance of 305 populations from 61 taxa by meta-analysis. They reveal strong population-level differentiation in marine and intertidal taxa, but not terrestrial or freshwater taxa, and highlight the need to consider such variation in climate vulnerability predictions.