North Indian Ocean sea level has shown significant increase during last three to four decades. Analyses of long-term climate data sets and ocean model sensitivity experiments identify a mechanism for multidecadal sea level variability relative to global mean. Our results indicate that North Indian Ocean sea level rise is accompanied by a weakening summer monsoon... Continue Reading →
El Niño-like teleconnection increases California precipitation in response to warming
Future California (CA) precipitation projections, including those from the most recent Climate Model Intercomparison Project (CMIP5), remain uncertain. This uncertainty is related to several factors, including relatively large internal climate variability, model shortcomings, and because CA lies within a transition zone, where mid-latitude regions are expected to become wetter and subtropical regions drier. Here, we... Continue Reading →
Future loss of Arctic sea-ice cover could drive a substantial decrease in California’s rainfall
From 2012 to 2016, California experienced one of the worst droughts since the start of observational records. As in previous dry periods, precipitation-inducing winter storms were steered away from California by a persistent atmospheric ridging system in the North Pacific. Here we identify a new link between Arctic sea-ice loss and the North Pacific geopotential... Continue Reading →
An energetic perspective on United States tropical cyclone landfall droughts
The 2017 Atlantic hurricane season has been extremely active both in terms of the strength of the tropical cyclones that have developed and the amount of storm activity that has occurred near the United States. This is even more notable as it comes at the end of an extended period of below normal U.S. hurricane... Continue Reading →
Increased rainfall volume from future convective storms in the US
Mesoscale convective system (MCS)-organized convective storms with a size of ~100 km have increased in frequency and intensity in the USA over the past 35 years, causing fatalities and economic losses. However, their poor representation in traditional climate models hampers the understanding of their change in the future. Here, a North American-scale convection-permitting model which is... Continue Reading →
Deep oceans may acidify faster than anticipated due to global warming
Oceans worldwide are undergoing acidification due to the penetration of anthropogenic CO2 from the atmosphere. The rate of acidification generally diminishes with increasing depth. Yet, slowing down of the thermohaline circulation due to global warming could reduce the pH in the deep oceans, as more organic material would decompose with a longer residence time. To... Continue Reading →
A pan-tropical cascade of fire driven by El Niño – Southern Oscillation
The El Niño/Southern Oscillation (ENSO) has a pronounced influence on year-to-year variations in climate. The response of fires to this forcing is complex and has not been evaluated systematically across different continents. Here we use satellite data to create a climatology of burned-area and fire-emissions responses, drawing on six El Niño and six La Niña... Continue Reading →
Drought conditions will maintain across a significant portion of the contiguous United States during December 2017
According to the US monthly drought outlook issued by NOAA CPC in November 30, the current severe drought conditions will maintain over the southern US. This is likely due to the developing La Nina condition in the Pacific. During La Niña, the winter atmospheric jet stream in the Pacific often takes an unusually wavy path... Continue Reading →
Highlights of the findings of the U.S. global change research program climate science special report
This executive summary presents the Fourth National Climate Assessment (NCA4), an authoritative assessment of the science of climate change, with a focus on the United States. This represents the first of two volumes of the Fourth National Climate Assessment, mandated by the Global Change Research Act of 1990. https://science2017.globalchange.gov/chapter/executive-summary/