So What Do Climatologists Do Anyways?

This year’s Climate and Society class is out in the field (or lab or office) completing a summer internship or thesis. They’ll be documenting their experiences one blog post at a time. Read on to see what they’re up to.

Cory Phillips, C+S ’17

“What the hell does a climatologist do?!” “Isn’t everything already understood about climate, and aren’t climatologists simply curators of meteorological history? “Weren’t climatologists borne out of the climate change ‘movement?’” “Al Gore lied!” “Chemtrails are the real problem!” “Do you study HAARP?”

I hear a lot of these questions and remarks like these. In fact, if you have a sick penchant for scrolling through the comment sections of online news like I do, you’ve read all about the misconceptions people have about the field of climatology. Is a climatologist a weatherman, as my comedian roommate always jokes? Is a climatologist a “libtard environmentalist,” crusading against climate change to force a global-elite agenda down hard-working American’s throats like my Uncle Steve insists?

I’ve been hard pressed to find out. This summer was my chrysalis. I vowed to become a climatologist, and I now have the tools to explain.

Much of my work involved analyzing temperature and precipitation data, using maps and statistics to tease out the relationships between sea-surface temperatures and global precipitation patterns and among regions of connected phenomena.

Climate models are probably the most fundamental tool advancing the field today, and to me, until recently, the models seemed like some large mythic machine behind locked doors in some secret facility in the desert. My research internship succeeded at demystifying them. They’re essentially mathematical representations of the climate system courtesy of codes run on powerful computers.

There is great confidence in models because they’re fundamentally based on established physical laws, such as conservation of mass, energy and momentum, and combined with on the ground and satellite observations. Like maps, they are actual representations of the planet, but they represent the complex physical activity that characterizes the atmosphere and the oceans.

These well-documented mathematical equations and physical formulas are ground truthed by being fed initial weather conditions and run to see if they recreate observed data, a process known as hindcasting. Then they’re used to project forward to see what we can expect in the future. Once the hindcasting can be validated, the projections can be considered predictive.

Models have the ability to simulate important aspects of current climates, such as precipitation, temperature, wind movement, air pressure, and regional phenomena like the monsoons. Because these processes can be simulated so well, scientists believe models can give us worthwhile insight into future climates, especially larger scale circulation models.

These models’ ability to replicate past climates increases that confidence. Yet despite their strength, many significant errors still exist. Usually these errors come from need to approximate important and complex, multifaceted small-scale processes effectively in the models. El Niño-Southern Oscillation (ENSO) is one phenomenon scientists are trying to model better. It’s responsible for causing natural shifts in climate around the world known as teleconnections.

Contour map of the correlation between sea-surface temperatures in the Niño 3 region (eastern tropical Pacific) and global precipitation. Higher correlations (toward the red) signify areas where precipitation increases with SST.

One such project, the Coupled Model Intercomparison Project (CMIP5) was my focus this summer. CMIP5 is the newest phase of a project that involves the climate science global community in testing and strengthening a modeling framework. Its results have been integral to the IPCC’s Fifth Assessment Report, and will be fundamental in preparing the sixth edition. These reports are the state of the art of climate studies and are crucial to informing national and international policies regarding the future of sensitive resources, sea levels, and extreme events.

The project has supplied a suite of different models and model iterations for evaluation. It is important to assess the mechanisms responsible for differences among the models, so I compared the performance of 47 CMIP5 ocean-atmosphere coupled global circulation models in reproducing global ENSO teleconnections since 1900. By establishing where on Earth there is agreement among simulations in all models, I could see what of these representations is effective and where disagreement points to less-understood mechanisms.