AMOC and AMV variability in different models
Underestimated AMOC variability in climate models has broad implications

Using both observations and simulations from multiple models, researchers show that most models underestimate the amplitude of low-frequency AMOC variability.

Hurricane Harvey and 2016 Louisiana Flood
Extreme event deja vu: Hurricane Harvey (2017) and Louisiana flood (2016)

Regional model simulations suggest that post-1980 warming in both the ocean and atmosphere resulted in an estimated 20% increase of the accumulated precipitation for Hurricane Harvey.

MOC time series at 34.5S
Dynamic and complex variability of the Atlantic Meridional Overturning Circulation at 34.5S

An international team of scientists used six years of simultaneous moored observations with satellite winds to produce a new MOC volume transport record for 34.5°S in the South Atlantic Ocean.

RAPID and MOVE arrays in the Atlantic Ocean
AMOC observations reveal coherent changes

Scientists have investigated differences between two arrays (at 16N and 26N) and found that both datasets show deep waters (below 1100 m) at the western boundary becoming fresher and less dense, but there remain discrepancies in the methods measuring ocean circulation. 

Sensible heat and evaporation fluxes in the Arctic Ocean
Arctic sea ice reductions influence air-sea energy exchanges

Researchers conclude that changes in sensible heat transfer and evaporation fluxes — in response to strong regional trends in sea ice cover — are becoming increasingly consequential to Arctic climate variability and change.

Changes in SST variance of ENSO
Is El Niño really changing?

ENSO experienced a regime shift in the late 1970s, after which events become stronger and less frequent. Researchers now conclude that the regime shift did not occur by chance but was due to a “real” change in the ENSO system.

Welcome to the US Climate Variability and Predictability Program

Webinar on tropical belt widening on June 27

Join us on June 27 at 1:00 pm ET for our next webinar in the Variations series on "Expansion of the tropics." This webinar will feature contributors to our most recent edition.

Learn about Climate Process Teams

Internal ocean mixing CPT

For a decade and a half, US CLIVAR has promoted the concept of Climate Process Teams (CPTs). CPTs are a useful way to transfer process-oriented research into climate model development. The history of CPTs, key lessons from past efforts, and how to propose future projects are outlined on the website.

Variations Spring 2018: Expansion of the tropics

Variations cover

The most recent edition of Variations is themed "Expansion of the tropics" and focuses on the magnitude, cause, and impacts of the recent expansion of the tropical belt region. The articles present some of the most pressing research questions, ideas for standardizing methods, the role of anthropogenic and natural variability, and how widening varies by region with different impacts over land and the ocean.

AMOC Science Team Report

AMOC Science Team Report Cover, sea ice

In its 10th year, the US AMOC Science Team report captures progress on the main objectives of the program, identifies new programmatic gaps,  provides near- and long-term research priorities, and outlines activities leading up to the sunset of the team. 

TPOS 2020 workshop presentations and posters

TPOS 2020 workshop participants

Over 50 participants gathered in Boulder, Colorado, on May 1–3 to discuss pathways for bridging observations to data assimilation for understanding the tropical Pacific, as part of the TPOS 2020 project. The presentations and posters presented during the workshop are available online for viewing. A workshop summary and report will be forthcoming. 

Process Study webinar series for 2018

cloud convection

The PSMI Panel is organizing a webinar series on proposed and current process studies starting in April 2018. The goals of this series are to provide feedback on the process study/field campaign plans and distill programmatic lessons learned. The webinars are open to the entire community. 

US CLIVAR celebrates 20 years

US CLIVAR 20th  anniversary

For the past 20 years, the US CLIVAR program has addressed some of the most pressing research questions to understand the climate system, particularly the great uncertainties related to the role of the ocean. To recognize the community and build on achievements, the program will host several events throughout the year.