The team, led by Mohammad Merheb of Institut Agro and INRAE in Rennes, France, together with colleagues from Montpellier and Imperial College London, assembled a database of 3,507 individual hydrometeorological records drawn from existing historical databases and published compilations. The sources behind these records are remarkably diverse. They include the annals of court chroniclers such as Ibn Al-Qalanisi of Damascus, who died in 1160, and Ibn Kathir, who wrote in the fourteenth century, as well as diaries like that of Ibn Tawq, a fifteenth-century Damascene whose daily jottings yielded more than 7,000 climate and environmental observations for the years 1481 to 1501 alone. Other records come from compilations of natural disasters in the medieval Levant and Egypt, and from coded datasets such as the Grotzfeld collection, which spans the Near and Middle East from 801 to 1821 CE.

Raw historical quotations, however, are not climate data. The core methodological achievement of the study lies in harmonization. Each of the 3,507 records was standardized according to three dimensions: the type of event described, whether drought, flood, heavy rainfall, or another hydrometeorological phenomenon; an intensity index that translates qualitative descriptions into a semi-quantitative scale; and the geographic location of the observation. This unified structure allowed the researchers to aggregate event frequencies by decade and to assess how well documented each period and place actually was. That coverage assessment matters enormously, because historical archives are notoriously biased toward times and places where literate elites had both the incentive and the leisure to write things down.

The spatial and temporal unevenness the team uncovered is striking. Documentation is densest and most continuous in Damascus, a city whose long tradition of chronicling, from Ibn Al-Qalanisi through Ibn Tulun in the early sixteenth century, produced an exceptionally rich written memory of weather and water. Other parts of the Levant appear only sporadically, often only when a disaster severe enough to merit mention struck. This unevenness shapes what the dataset can and cannot do. For most of the region and most of the period, the records offer snapshots rather than continuous series. But for Damascus between 1250 and 1520 CE, the density of long-term precipitation and flood records is sufficient to analyze variability at the decadal scale, and in some cases even at the seasonal scale.

The crucial test came when the researchers compared their documentary evidence with an independent, physically based source of paleoclimate information: the Old World Drought Atlas, or OWDA, a tree-ring-based reconstruction that provides summer Palmer Drought Severity Index values, or PDSI, across Europe, the Mediterranean and the Middle East for the past two millennia. Tree rings encode moisture stress in their growth rings, giving annually resolved reconstructions that are completely independent of what any medieval scribe wrote. If the two archives disagree systematically, the documentary records might reflect local anecdote, literary convention, or copying errors rather than real climate. If they agree, both are likely capturing genuine hydroclimatic signal.

To make the comparison rigorous, the team derived a dryness index directly from the historical descriptions, classifying episodes of drought and water scarcity recorded in the texts, and then evaluated the relationship between the documentary index and the OWDA-derived PDSI for Damascus using conditional probability. The analysis showed relative coherence between the two datasets: when the chronicles reported dry conditions, the tree rings tended to indicate drought as well, and vice versa. This agreement is significant because it validates, for the Levant, an approach that historical climatologists have applied successfully in Europe and China but that has remained comparatively underdeveloped in the eastern Mediterranean, where the documentary traditions, languages and archival conditions differ substantially.

One of the most intriguing findings emerged from the seasonal analysis of the historical records. Most of the dry episodes documented in the texts occurred during the winter and autumn rainy seasons, the very months on which the Levant depends for nearly all of its annual precipitation. In a region with a Mediterranean climate, where summers are reliably dry and agriculture hinges on the October-to-May rainy season, a failure of autumn or winter rains is not a minor inconvenience but a threat to harvests, water supplies and, historically, to political stability. The chronicles’ emphasis on these events suggests that medieval observers were recording precisely the hydrometeorological anomalies that mattered most to their societies, which in turn makes their testimony especially valuable for reconstructing drought variability.

The study’s implications reach beyond medieval history. The Levant is one of the world’s most water-stressed regions today, and climate projections generally indicate increasing aridity and greater hydrological variability in the decades ahead. Understanding how precipitation and drought behaved over the past sixteen centuries provides a baseline against which modern changes can be measured, and it extends the observational record far beyond the instrumental era, which in this region barely stretches back a century. Documentary records can also capture extreme events, such as destructive floods, that may be poorly represented in tree-ring reconstructions, which respond primarily to moisture stress rather than to individual episodes of heavy rainfall.

The authors are candid about the limitations that remain. The spatial distribution of surviving documents is highly uneven, concentrating evidence in a handful of urban centers while leaving much of the rural Levant in darkness. Many potential sources remain inaccessible or unexamined, and unlocking them requires proper curation by historians with the linguistic and paleographic skills to read Arabic, and other historical manuscripts in their original forms. The study is, in this sense, as much an argument for interdisciplinarity as it is a climate reconstruction: without collaboration between hydrologists and historians, a large fraction of the region’s environmental memory would stay locked in archives that scientists rarely visit.

Even with those caveats, the research demonstrates that fragmented documentary evidence, when systematically harmonized and analyzed, can yield partially consistent, semi-quantitative indicators of past hydroclimatic variability. The 3,507 records compiled here represent a foundation that can be expanded as more chronicles are transcribed, translated and coded, and as datasets like tambora.org continue to grow. For a region whose water future is uncertain, the meticulous observations of medieval scribes, cross-checked against the silent testimony of tree rings, offer a rare and precious long view of drought and flood, one written in ink but verified in wood.

Subject of Research: Historical documentary records of hydrometeorological events in the Levant compared with paleoclimate reconstructions

Article Title: Characterization of hydrometeorological events from historical records in the Levant (200–1850 CE) compared to paleoclimate reconstructions

Article References: Merheb, M., Moussa, R., Hamelin, G., Lemoine, N., & Cudennec, C. (2026). Characterization of hydrometeorological events from historical records in the Levant (200–1850 CE) compared to paleoclimate reconstructions. Regional Environmental Change, 26(4), Article 200. https://doi.org/10.1007/s10113-026-02693-w

Image Credits: AI Generated

DOI: 10.1007/s10113-026-02693-w

Keywords: historical climatology, Levant, Damascus, drought, floods, Palmer Drought Severity Index, Old World Drought Atlas, documentary sources, paleoclimate reconstruction, medieval chronicles, hydrometeorology, Regional Environmental Change

The research by Thomas Fetzer and Piyush Garg examines how disasters cross the boundary between a domestic event and a global news story. When a catastrophe occurs, journalists and editors must decide whether it matters to audiences in other countries. That decision is rarely based on physical damage alone. A disaster may become internationally prominent when it affects a strategically important country, involves foreign citizens, disrupts trade or transport, or occurs in a place that already receives extensive media attention. By contrast, equally severe events in less connected or less frequently covered regions can struggle to attract sustained reporting.

To investigate this pattern, the researchers compare information about natural disasters with the volume and distribution of media coverage across countries. Such an approach allows them to distinguish between the occurrence of a disaster and its visibility in the international information system. Disaster databases can record characteristics such as location, timing, hazard type and human consequences, while large-scale news archives can reveal which countries report on an event, how often they do so and how quickly coverage appears. The comparison provides a way to measure what might be called cross-border media attention: reporting generated outside the country where the disaster occurred.

The technical challenge is that media coverage is not a simple count of articles. A single event may be reported repeatedly by international wire services, translated into several languages, republished by local outlets or mentioned briefly in broader stories. Researchers therefore need to account for duplication, differences between national media systems and variations in the amount of news produced in each country. Statistical models can then estimate how much coverage would be expected from the severity and location of a disaster, while testing whether other factors explain why some events receive more attention than others. This framework turns an apparently subjective question—why did one disaster become global news?—into a measurable problem.

The study’s central message is that international reporting follows an uneven geography. Countries are not equally visible to one another, even when they experience comparable hazards. Media attention tends to be stronger where nations are geographically close, economically connected or linked by political and social relationships. Shared borders can make a disaster more newsworthy because audiences may fear consequences at home, while trade and investment ties can raise the perceived importance of disruption abroad. Historical relationships, migration links and the presence of foreign nationals may also create editorial incentives to follow an event more closely.

This does not mean that the physical scale of a disaster is irrelevant. Large death tolls, extensive displacement and damage to infrastructure can all increase the probability that a disaster will be covered internationally. Events that threaten major cities, affect energy supplies or interrupt transportation networks may also generate rapid attention. But the analysis indicates that impact alone does not determine visibility. Two disasters with similar consequences can produce very different patterns of international reporting, depending on where they occur and which countries are watching. In this sense, the global news system filters humanitarian emergencies through a network of national interests.

The imbalance has consequences beyond public awareness. Media coverage helps determine which crises become subjects of political debate, charitable appeals and international assistance. When an event receives little reporting abroad, audiences in wealthier or more distant countries may never learn its scale, and policymakers may face less pressure to respond. Visibility can therefore become an indirect resource, distributed according to connections that have little to do with need. The result is a potential gap between the geography of suffering and the geography of attention: the places experiencing the greatest hardship are not necessarily the places most likely to appear in foreign news.

The findings also illuminate how modern news ecosystems can amplify existing inequalities. International outlets frequently depend on wire services, established correspondents and local partners. These networks make it easier to report from countries where media organizations already have staff, reliable communication channels and institutional familiarity. In regions with limited news infrastructure, censorship, language barriers or weak digital connectivity, information may arrive more slowly or be harder to verify. Algorithms on search engines and social-media platforms can further reinforce the pattern by promoting stories that already attract engagement, causing early visibility to snowball into even greater visibility.

For scientists and humanitarian organizations, the research offers a warning about using media attention as a proxy for disaster importance. News counts are sometimes treated as indicators of public concern, crisis severity or international salience, but they may reflect the structure of global relationships as much as the underlying event. A better monitoring system would combine journalistic data with independent measures of damage, mortality, displacement and recovery needs. Automated tools such as natural-language processing could help identify underreported disasters across languages, while satellite observations and local reporting could provide evidence when international coverage is sparse.

The study does not suggest that every disaster should receive identical coverage or that news organizations can eliminate editorial judgment. Rather, it shows that the pathways through which information travels are systematically unequal. Recognizing those pathways may help editors, platforms and aid agencies ask a crucial question before the next catastrophe: is this event receiving attention because it is exceptionally severe, or because it occurred in a country the world is already prepared to watch? In an era of intensifying climate hazards and increasingly interconnected economies, answering that question could determine which disasters become global emergencies—and which remain largely unseen.

Subject of Research: Uneven cross-border media coverage of natural disasters and the factors shaping international news attention.

Article Title: Uneven patterns of cross-border media coverage following natural disasters

Article References: Fetzer, T., Garg, P. Uneven patterns of cross-border media coverage following natural disasters. Nature Human Behaviour (2026). https://doi.org/10.1038/s41562-026-02512-6

Image Credits: AI Generated

DOI: https://doi.org/10.1038/s41562-026-02512-6

Keywords: natural disasters, cross-border media coverage, international news, media attention, disaster inequality, global communication, humanitarian response, news visibility

One key analysis targets how the growing frequency of heatwaves and drought conditions affects access to food. Led by CMCC researcher Shouro Dasgupta and Professor Elizabeth Robinson at the Grantham Research Institute, the study connects climate signals to nutrition outcomes using an empirical approach. Heatwave-day and drought-month anomalies are calculated relative to a baseline period of 1981–2010, then matched with food security data to quantify shifting risk over time.

In 2023, the researchers estimate that an additional 2.7 million people—about 4.9% of the combined population of 26 SIDS, roughly 70 million people total—experienced moderate or severe food insecurity due to more frequent heatwaves and droughts. The results suggest a measurable climate-to-food pathway: higher heatwave-day frequency correlates with 5.74% higher moderate or severe food insecurity, while increasing drought frequency is associated with a 3.53% rise.

The report also highlights that vulnerability is amplified by structural constraints. Many SIDS rely heavily on food imports, so climate shocks that damage infrastructure or interrupt trade can rapidly translate into shortages and price spikes. In such settings, climate risk becomes an economic and health risk at the same time, particularly when fiscal space is limited.

Beyond food insecurity, climate impacts are showing up in broader health costs. In 2024, SIDS lost the equivalent of 1.27% of GDP due to reduced labor capacity—higher than the global figure of 0.99%. Over the early 2000s, heat-related mortality costs have increased by 432%, the steepest increase among tracked groups.

The study strengthens the case that climate action is not only about emissions but also about preventing cascading harms. It also aligns with the policy argument that limiting warming to 1.5°C is legally binding and that accountability may arise where causation to climate damage is established. For SIDS, the clock is accelerating—and the costs are showing up first.

Subject of Research: Health and climate impacts in Small Island Developing States, with a focus on climate-driven food insecurity
Article Title: 2025 Small Island Developing States report of the Lancet Countdown on health and climate change
News Publication Date: 2025
Web References: Not provided
References: Lancet Countdown (2025) report; FAO; CMCC / LSE research collaboration
Image Credits: Not provided

Keywords: Small Island Developing States, climate change, food insecurity, heatwaves, droughts, food imports, health costs, Lancet Countdown