A new study by climatologists at the University of Michigan concludes that some of the latest generation climate models may be overly sensitive to increases in carbon dioxide and therefore project unrealistic future warming. In a letter scheduled for publication April 30 in the journal Natural climate change, the researchers say that projections from one […]
Source: Journal of Advances in Earth Systems Modeling (JAMES) Weather and climate models have improved dramatically in recent years, as progress in one area has tended to benefit the other. But there is still significant uncertainty in the model outputs that are not precisely quantified. Indeed, the processes that govern climate and weather are chaotic, […]
Source: Earth and Space Sciences The clouds play a important role in the Earth’s climate and can warm or cool the atmosphere depending on their particular characteristics and when and where they form. Computer models of Earth’s future climate suffer from uncertainties related to the challenge of predicting cloud cover and how the effects of […]
A handful of climate projections predict a rise in global temperatures much higher than what scientists have seen in previous models. Although the number raises concerns, some scientists hope the latest projections are outliers. A 2 degree rise in temperature could lead to rising sea levels, the death of coral reefs and dangerous water scarcity […]
Prior to each Intergovernmental Panel on Climate Change (IPCC) report, the Global Climate Modeling Centers produce a central database of standardized simulations. Over the past year, an interesting trend has emerged in the most recent round of this effort: the newer and better versions of these models are, on average, more sensitive to CO2, warming […]
Climate skeptics have long questioned the accuracy of computer models that predict global warming, but most early climate models turn out to be spot-on, according to a flashback from University of California climatologists at Berkeley, Massachusetts Institute of Technology and NASA. Of 17 climate models published between the early 1970s and late 2000s, 14 were […]
A recent to study computer climate models dating back to the 1970s have shown them to be very accurate in relation to what actually happened over the following decades. This builds confidence in modern models that predict further changes in the future. In the 1970s, climatologists began to report the increasing amount of carbon dioxide […]
In climate science, models are essential tools in trying to understand an uncertain future. But attempts to predict the future are easy targets, and climate change skeptics have long sought to poke holes in past climate change predictions to undermine the credibility of today’s dire warnings. Now a full review of climate models dating back […]
It’s a common refrain from those who question the findings of climate science: the computer models scientists use to project future global warming are inaccurate and shouldn’t be trusted to help policymakers decide whether to they must take potentially costly measures to limit greenhouse gas emissions. A new study effectively quells this argument by examining […]
There’s a favorite argument among those who doubt mainstream climate science: climate models overestimate the rate at which the Earth is warming. This claim resurfaces time and time again and is often based on single instances of uncertainty or hand-picked data. Various studies have looked closely at individual climate models in recent years and have […]
A new study finds that past computer simulations of climate change have been quite accurate. Credit: Associated Press Computer models used to simulate the effects of heat-trapping gases on global temperatures have been quite accurate in their predictions, according to a new study. After years of hearing reviewers criticize the models’ accuracy, climatologist Zeke Hausfather […]
This color-coded map shows global surface temperature anomalies. Temperatures above normal are shown in red and temperatures below normal are shown in blue. (NASA Goddard Space Flight Center) Of the 17 climate change models examined, 14 were accurate enough to predict the effects of global warming. The researchers fed the actual emission levels into the […]
A new paper by Hausfather and his colleagues (including me) has just been published with the most comprehensive assessment of climate model projections since the 1970s. Bottom line? Once you fixed the small errors in the projected overrides, they performed remarkably well. Climate models are central to our understanding of our future climate. They have […]
UNIVERSITY PARK, Pennsylvania — Equilibrium climate sensitivity — the sensitivity of Earth’s climate to changes in atmospheric carbon dioxide — may be underestimated in individual climate models, according to a team of climatologists. “Probabilistic estimates of climate system properties often rely on comparing the model simulation with observed temperature records and an estimate of internal […]
Katharine Hayhoe knows that climate models are not perfect. “The more you know about models, the less you trust them and the more you blow their tires,” says Dr. Hayhoe, co-director of the Climate Science Center at Texas Tech University. Why we wrote this When planning for the future, certainty can be hard to come […]
Computer models of the climate are at the heart of calls to ban the cheap, reliable energy that powers our thriving economy and promotes healthier, longer lives. For decades, these models have projected dramatic warming small fossil increases in atmospheric carbon dioxide concentrations, with catastrophic consequences. Yet real-world data doesn’t cooperate. They only show a […]
Chaos theory encompasses vast swaths of mathematics and physics, but it was Edward Lorenz who immortalized it in popular culture. Its now famous 1972 presentation, which summarized his decade-long work in the field, focused on a single provocative question: Can the flapping of a butterfly’s wings in Brazil trigger a tornado in Texas? Although he […]
A new reconstruction of global mean surface temperature trends over the past 2,000 years has identified the major causes of decade-scale climate change. The analysis suggests that the Earth’s current rate of warming, caused by human emissions of greenhouse gases, is greater than any previously observed rate of warming. The researchers also found that airborne […]
[ad_1] According to a recent paper published on July 3 in the journal Scientists progress (1). For example, in 1983, ENSO was responsible for the largest synchronous harvest failure in recorded modern history. Globally synchronous harvest failures refer to the simultaneous failure of a single harvest in several as far apart as the United States, […]
Source: Geophysical Research Letters One of the most difficult questions regarding climate change is how the warming of the Earth’s atmosphere will affect water availability around the world. Climate models present a range of possible scenarios, some more extreme than others– which can complicate planning for cities, states and countries. Now, however, in a new […]
Professor Stephen Belcher is Chief Scientist at UK Met Office; Doctor Olivier Boucher is at the head of Pierre Simon Laplace Institute (IPSL) Climate Modeling Center; and Professor Rowan Sutton is director of climate research at UK National Center for Atmospheric Sciences (NCAS), Reading University. The first results of a new generation of global climate […]
According to an international team of researchers from 17 countries. The results published last week in nature geoscience are based on observational evidence of three warm periods over the past 3.5 million years, when the world was 0.5°C to 2°C warmer than pre-industrial temperatures in the 19th century. The research has also revealed how large […]
Designing climate experiments is nearly impossible in the real world. We cannot, for example, study the effects of clouds by removing all the clouds for a set period of time and seeing what happens. Instead, we have to design our experiments virtually, by developing computational models. Now a new open-source set of climate models has […]
[ad_1] Computer climatologist Salil Mahajan simulates the complex and chaotic aspects of the climate at the Oak Ridge National Laboratory. (Photo by ORNL / US Department of Energy) By Ashley C. Huff, Oak Ridge National Laboratory High resolution global climate simulation at multiple scales will help answer questions about future global and regional climates. However, […]
[ad_1] This figure shows the characteristic “horseshoe” model of Atlantic climate variability (upper left panel), as well as the temporal history of this model (lower left). Most of the previous studies attribute this to changes in ocean circulation. Our study compares climate models that include ocean circulation (top right) with climate models that do not […]