With anthropogenic climate change becoming evident, it is imperative to provide reliable scientific information to society on causes of emerging trends. Sea level pressure (SLP) is a key variable, relevant for impacts and extremes (e.g., steering flows for storms, storm track changes), for which trends and other changes must be monitored and understood. This study explores how the atmospheric circulation may be changing regionally in response to anthropogenic forcing, based on an analysis of sea level pressure trends in observations and models. Read More…
GFDL Research Highlights
October 21st, 2020 - Estuarine forecasts at daily weather to subseasonal time scales
Estuary and coastal ocean forecasts based on predictions of temperature, salinity, currents, and storm surge have been shown to be able to protect lives and property from storm surge, assist search and rescue operations, and protect public health. These forecasts enable predictions of harmful algal blooms and the dispersion of oil spills. Many estuaries are also home to ecologically and economically important ecosystems and fisheries, and forecasts may also be useful for improving the management of fisheries and locating ideal fishing spots. This research demonstrates that temperature and salinity can be skillfully forecast at both the bottom and surface levels of an estuary up to two weeks in advance. Read More…
The authors describe a systematic evaluation of GFDL’s new 50km high-resolution version of the AM4 atmospheric model, for its ability to simulate atmospheric river (AR) characteristics including climatology, variability and future change. This study is relevant for assessing the model’s ability to simulate and predict weather and climate extremes such as flood, drought and extreme winds. Read More…
October 7th, 2020 - GFDL SHiELD: A Unified System for Weather-to-Seasonal Prediction
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…
September 24th, 2020 - Increased risk of the 2019 Alaskan July fires due to anthropogenic activity
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…
July 24th, 2020 - Projected Changes in South Asian Monsoon Low-pressure Systems
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…
June 2nd, 2020 - A mechanism for the Arctic sea ice spring predictability barrier
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…
May 4th, 2020 - Detected Climatic Change in Global Distribution of Tropical Cyclones
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…
April 22nd, 2020 - Tropical Cyclone Motion in a Changing Climate
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…