At many weather forecasting centers, different computer weather models are run for different applications. In the U.S., there are separate models for short-range, long-range, seasonal, and hurricane forecasting. Each specialized model is designed by different experts to get the best results. However, having separate models multiplies the effort needed to maintain and upgrade each model, and makes it difficult to move improvements from one model to another. Read More…
Extreme wildfires have increased in Alaska, affecting the economy and public health of an entire region. The authors assessed the influence of anthropogenic activities on extreme fires in Alaska, taking advantage of the modeling capability of GFDL’s Earth System Model (ESM4.1) to simulate the complex interactions between fire, climate, land ecosystem, and human activity. Their findings indicate that a three-fold increased risk of Alaska’s extreme fires during recent decades can be attributed to primarily anthropogenic ignition and, secondarily, climate-induced biofuel abundance. By sorting out controlling factors of wildfires in Alaska, this modeling study improves our understanding of the impact of climate change on wildfires in Alaska, enabling better predictions. Read More…
Monsoon low-pressure systems (MLPSs) are the primary rain-producing synoptic-scale systems over the Indian subcontinent, and are estimated to be responsible for more than half of the annual precipitation in agrarian North and Central India. Changes in the characteristics of MLPSs, whether natural or forced, have far-reaching socio-economic impacts. Understanding future changes in MLPSs and associated rainfall is a necessary step toward projecting flood or drought risks in a warmer climate. Read More…
Observations over the past 40 years have documented a significant decline in Arctic sea-ice extent and thickness. These rapid changes and their implications for Northern communities, shipping industries, wildlife, fisheries, and natural resource industries have created an emerging operational need for regional summer sea-ice predictions. Read More…
Although global mean temperature has been rising since the mid-twentieth century and can be attributed to increases in emissions of greenhouse gasses, the annual number of global tropical cyclones (TCs) has remained steady at around 86 since 1980. The limited length of observed TC data and the effect of multi-decadal variability have made it challenging to detect trends in TC activity on a global scale. Read More…
There is intense public and scientific interest in the question of whether slowly moving and highly destructive hurricanes, such as Harvey (2017), Florence (2018), and Dorian (2019), could become much more common with climate change. Using high-resolution large ensemble simulations, the authors investigated whether future anthropogenic warming could lead to a significant slowing of hurricane motion, and whether the observed trends of hurricane motion during past decades could be attributed to anthropogenic forcing. Read More…
Ground-level ozone exposure harms human and plant health, especially on hot summer days when pollution from cars and power plants fuels ozone formation. Due to regulatory changes, emissions of ozone precursors have been reduced markedly in Europe, yet ozone pollution episodes have not decreased satisfactorily in recent decades. The authors show that slow progress towards improving ozone air quality in Europe can be partly explained by declining rates of ozone removal by water-stressed vegetation in response to climate warming. Read More…
The models in use at GFDL for seasonal-to-decadal prediction have performed very well but are built off rather old model physics and other components. A multi-year effort was undertaken to build a next-generation seasonal-to-decadal prediction system that took advantage of many recent modeling advancements. This effort culminated in a new modeling system called the “Seamless system for Prediction and EArth system Research” (SPEAR). Read More…
High Mountain Asia is home to both monsoonal rains and the largest concentration of glaciers outside the North and South Poles. With climate change, heavy rainfall will increase, especially in mountains near glaciers and glacial lakes. This will make landslides more likely and could present new hazards of landslides releasing a wall of water from glacial lakes, impacting communities and infrastructure located downstream. Read More…
Changes in atmospheric methane abundance have implications for both chemistry and climate, as methane is both a strong greenhouse gas and an important precursor for tropospheric ozone. The global network of methane surface observations over the past 3-4 decades indicates that methane went through a period of rapid growth from the 1980s to 1990s, nearly stabilized from 1999 to 2006, and then renewed its rapid growth. Read More…
