Today is World Water Day

Each year, World Water Day is held on the 22nd of March as an international means of emphasizing the importance of freshwater and advocating for the sustainable management of Earth’s water resources. According to UN Water, this year’s theme is International Year of Water Cooperation. Celebrations all over the globe are in full swing today. Check out the World Map of Events to get involved!

Want to broaden your understanding of water systems and sustainability? Our Princeton Primers in Climate series are the ideal first place to turn to get the essential facts and to begin further investigation–whether in the classroom or in one’s own reading chair.

k9635The Cryosphere by Shawn J. Marshall

Introduction to the cryosphere and the broader role it plays in our global climate system. Looks at each component of the cryosphere and how it works–seasonal snow, permafrost, river and lake ice, sea ice, glaciers, ice sheets, and ice shelves. Marshall describes how snow and ice interact with our atmosphere and oceans and how they influence climate, sea level, and ocean circulation.


RandallAtmosphere, Clouds, and Climate by David Randall

David Randall looks at how the atmosphere regulates radiative energy flows and transports energy through weather systems such as thunderstorms, monsoons, hurricanes, and winter storms. Randall explains how these processes work, and also how precipitation, cloud formation, and other phase changes of water strongly influence weather and climate.


Vallis - oceansClimate and the Oceans by Geoffrey K. Vallis

Offers a short, self-contained introduction to the subject. This illustrated primer begins by briefly describing the world’s climate system and ocean circulation and goes on to explain the important ways that the oceans influence climate. Topics covered include the oceans’ effects on the seasons, heat transport between equator and pole, climate variability, and global warming.


Celebrate World Water Day! Today, enlighten yourself and inform others about the sustainable management of the world’s water supply.


Q&A with Ian Roulstone and John Norbury, authors of Invisible in the Storm

We are publishing Invisible in the Storm by Ian Roulstone and John Norbury next month. The book explains how mathematics and meteorology come together to predict the weekly weather, prepare us for incredible weather events like Hurricane Sandy, and contribute to our understanding of climate change. They kindly answered a few of my questions for the Princeton University Press Blog:



1.      I’ll start with the thing everyone is talking about. It seems like extreme weather more prevalent in recent years. With Hurricane Sandy and the recent unprecedented Nor’Easter behind us (ed. note: I’m writing from NJ), it bears asking whether the future holds more extreme weather? Can mathematics help answer this question?

Mathematicians think about weather and climate in an unusual way. Our ever-changing weather can be visualized as a curve meandering through an abstract mathematical space of logically possible weather. Any one point of the curve corresponds to a particular state of the weather. The surprise is that the curve does not wander around randomly–patterns emerge. One part of the pattern may correspond to ‘warm and dry’ and another part to ‘cold and wet’. Predicting changes in the weather for the week ahead involves working out if the curve will drift from one part of the pattern to another. Understanding climate involves working out how the pattern itself will change.

2.      So, is the pattern changing toward more extreme weather or can we not answer this question yet?

If we compare the results from different climate models (from different research institutions and weather bureaus around the world), then they show an increase in global average temperature over the next century. However, this could lead to quite different conditions in different parts of the world. For example, if the Gulf Stream was weakened, Europe could experience colder weather. However, we know our models are not perfect, and mathematics is helping us to understand the errors that are inherent in the compuer-generated simulations. This work is important as it will help us to estimate the likely extremes in weather and climate with greater confidence.

3.      To return to the end of your first answer, how can mathematics detect climate change?

Climate depends on many factors: the atmosphere, the oceans, the icecaps, land usage, and life in all its forms. Not only are there many interconnections between these systems, the timescales over which changes occur vary enormously: trees can be felled in a few hours or days–changing the character of the local landscape quickly–but carbon stocks in soil vary much more slowly, perhaps over several millennia. To predict future climate we have to account for the short- and long-timescale effects, and this can pose subtle problems. Mathematics helps us to quantify how the different timescales of the changes in the components of the Earth system impact on predictions of climate change. Using mathematics, we calculate how cloud patterns change over the next five days, and how the Arctic ice-sheet changes over the next five years.

4.      How does mathematics help forecasters predict the weather for the week ahead? 

One of the main sources of information for a new forecast is yesterday’s forecast. New generations of satellites gather more, and more accurate, readings, ranging from the sea surface temperature to the state of the stratosphere. Data is exchanged freely around the world among weather bureaus; global weather prediction relies upon this protocol. However, we will never have perfect, complete weather data, and this is why we need mathematical techniques to combine the new information with the old.

5.      Years ago, it seems like weather was much simpler — will it rain, snow, sleet, or be sunny? These days, mathematics enables weather forecasters to forecast more than rain or shine: the computer simulations are useful for predicting everything from pollen levels and pollution to flood risk and forest fires. Can you explain how mathematics is part of this?

Mathematics is the language we use to describe the world around us in a way that facilitates predictions of the future. Even though hay fever and floods are very different natural phenomena, predictions of their occurrence can be made using mathematical models. Weather forecasters are actively engaged in combining their predictions with models that help us forecast weather-related phenomena.

6.      It sounds like a one-way street — mathematics helps us understand meteorology — but you note in the book that the relationship is more reciprocal. Can you elaborate?

To most of us, meteorology and mathematics are a world apart: why should calculus tell us anything about the formation of snowflakes? But mathematics has played an ever-growing and crucial role in the development of meteorology and weather forecasting over the past two centuries. Our story explains how mathematics that was originally developed for very different purposes, such as studying the ether or the dynamics of the solar system, is now helping us to understand the dynamics of the atmosphere and oceans, and the changes in our climate. And it is a two-way process: the diversity of phenomena we seek to quantify means we have to describe them using new mathematical ideas that capture the rapid changes, the slow changes, the randomness, and the order, we observe.

7.      Is there a current area of mathematical/meteorological research that you are particularly excited about? Ie – what’s next?

     There’s one particular subject that’s attracting a lot of attention right now: it is called data assimilation. This is the part of the forecasting process where new observational information about the state of the atmosphere is combined with the previous forecast, to give us the starting conditions for the next forecast. Improvements to this part of the forecasting process nearly always lead to better forecasts. And the technology applies to modelling the climate too. In this case, we’re not so much interested in whether we have the correct starting conditions, but whether we have used the correct values of the parameters that define the processes and physical phenomena which affect climate–for example, the carbon cycle, from leaves to biomass and carbon dioxide. One of the reasons this is a really exciting area for mathematicians is that we need some new mathematical ideas to analyse these problem. At the moment we rely heavily on math that was developed over 50 years ago–and it works very well–but as we strive to increase the detail we want to represent in our weather and climate models, we have to unravel the Gordian knot that ties together the many different parts of the Earth system we have to represent.


HOW CLIMATE WORKS (Part 9) — The Q&A session

Our video series on the HOW CLIMATE WORKS symposium held at Princeton University this past fall concludes with the Q&A session following the final talk of the day. We hope you have enjoyed your symposium vidoes. For furthur reading, check out our Princeton Primers in Climate series.

HOW CLIMATE WORKS (Part 8) — Caltech’s Andrew Ingersoll on Planetary Climates

Part 8 from the How Climate Works symposium brings us Andrew Ingersoll of the California Institute of Technology on planetary climates. This fall we will be publishing his book of the same toipc PLANETARY CLIMATES.

HOW CLIMATE WORKS (Part 7) — Shawn Marshall on The Cryosphere

Part 7 from the How Climate Works symposium features Shawn Marshall of the University of Calgary on the cryosphere. We published his excellent book on the subject in the Fall or 2011 called THE CRYOSPHERE.

HOW CLIMATE WORKS (Part 6) — Michael Bender on Paleoclimate

Continuing with our series on talks from Princeton’s HOW CLIMATE WORKS symposium, here we see Princeton University geoscience professor Michael Bender discussing Paleoclimate. His new book PALEOCLIMATE will be availble July 2013.

HOW CLIMATE WORKS (Part 5) — David Archer on the Global Carbon Cycle

Renowned University of Chicago geophysicist David Archer discussed the Global Carbon Cycle. We published the book of the same name, THE GLOBAL CARBON CYCLE, in the Fall of 2010.

HOW CLIMATE WORKS (Part 4) – The Morning’s Q&A Session

For those following our HOW CLIMATE WORKS symposium videos, our latest addition is the morning’s Questions & Answers session.

HOW CLIMATE WORKS (Part 3) – David Randall on Atmosphere, Clouds, and Climate

Part 3 from the HOW CLIMATE WORKS symposium here at Princeton University features David Randall, a professor of atmospheric science at Colorado State University. He discussed his Princeton University Press book ATMOSPHERE, CLOUDS, AND CLIMATE, published in Spring 2012.

Harvard Professor of Geochemistry Charles Langmuir celebrates the revised edition of the book that has introduced generations of readers to the science of Earth’s origin and evolution

“Life evolves in relationship with the planet, and progressively modifies it to form a single integrated system.”–Charles Langmuir

View the video from its original source at Harvard Museum of Natural History’s website:


How to Build a Habitable Planet:
The Story of Earth from the Big Bang to Humankind (Revised and Expanded Edition)


Charles H. Langmuir & Wally Broecker

Since its first publication more than twenty-five years ago, How to Build a Habitable Planet has established a legendary reputation as an accessible yet scientifically impeccable introduction to the origin and evolution of Earth, from the Big Bang through the rise of human civilization. This classic account of how our habitable planet was assembled from the stuff of stars introduced readers to planetary, Earth, and climate science by way of a fascinating narrative. Now this great book has been made even better. Harvard geochemist Charles Langmuir has worked closely with the original author, Wally Broecker, one of the world’s leading Earth scientists, to revise and expand the book for a new generation of readers for whom active planetary stewardship is becoming imperative.

“To be worth being this unwieldy, a book ought to do something pretty remarkable. And that’s just what How to Build . . . does, as you can tell from its subtitle, The Story of Earth from the Big Bang to Humankind. Now that’s what you call a large canvas.”–Brian Clegg, Popular Science

HOW CLIMATE WORKS (Part 2) — David Schimel on Climate and Ecosystems

Part 2 from the HOW CLIMATE WORKS symposium here at Princeton University features David Schimel, a senior reserach scientist at the Jet Propulsion Lab in Pasadena. He discussed his forthcoming Princeton University Press book CLIMATE AND ECOSYSTEMS, due out in June 2013 in our series Princeton Primers in Climate. In 2007, David was a corecipient of the Nobel peace Prize for his work on the Intergovernmental Panel on Climate Change’s first report on the global cabron cycle.

Check out his talk below.

HOW CLIMATE WORKS symposium, co-sponsored by Princeton University Press and the Princeton Environmental Institute

On October 12, 2012, Princeton University Press and the Princeton Environmental Institute hosted a day-long symposium titled HOW CLIMATE WORKS. The symposium was held in conjunction with the publication of our latest titles in the well-received Princeton Primers in Climate series.

In this first of ten segments to be posted here the symposium speakers discussed their contributions to the Princeton Primers in Climate series. The introduction remarks were given by Princeton University Press biological sciences editor Alison Kalett and Princeton professor Geoffrey Vallis, author of CLIMATE AND THE OCEANS.