One book · one website · one sky
Learn to read the sky, before you launch or head into the mountains
A book for understanding mountain weather without being a meteorologist, and a website for watching it move. Pierre Verley, a paraglider pilot and hiker, wrote it for those who fly and for those who walk: the same sky, read twice.
Start reading See the book move
The beginning of the book and all the quizzes are free · the ePub book, €6.99 · the site subscription, €3 a month
Where to start
Do you fly, hike, or both?
Three paths through the book, taken from the preface. Tell us yours: the site will remember it on this device.
You fly
Everything, in order. The heart of the craft:
You hike
The hurried hiker’s path:
You do both
The whole book, in order: it is written for those who fly and for those who walk. The evening before an outing:
- Forecasting in practice, for the method
- Twelve typical days, to recognise the day ahead
Leaf through the book
A figure looked at carefully is worth a page of text
From the cloud you learn to name to the day you learn to decide, the book moves forward through diagrams. Scroll along.
- 12 chapters
- 138 figures
- 56 animations
- 143 questions
- 9 games
Prelude · Clouds FreeThe ten cloud genera at their levels, from stratus to the cumulonimbus flattened against the tropopause.
Chapter 1 · Air FreeAt the summit of Mont Blanc, you have already left nearly 45% of the air below your feet.
Chapter 2 · The emagram FreeThe rails are printed in advance; only the day’s two curves change from one sounding to the next.
Chapter 6 · Terrain 🔒On the windward side, the air rises: the ridge-lift zone. In the lee, it comes back down.
Chapter 7 · Breezes 🔒The breeze clock: the slopes switch over quickly, the valley follows with a delay.
Chapter 8 · Thermals 🔒The thermal slants: downwind of its source, upwind of the cloud it feeds.
Chapter 9 · Hazards 🔒The signal to act is the tower that is taller than it is wide, not the first lightning flash.
Chapter 11 · The workshop 🔒Twelve typical days on a single map: the ideal slot is narrow.
In every chapter: The essentials in two minutes Why? Pitfall In flight Hiker’s reflex Your turn
The workshop
You read the book; here, you can handle it
Set the animation to the values in the question, just below: the bubble rises, the cloud settles at the base, and you read off the altitude. It is Figure 1.6 of the book, in motion. 56 figures have an animation like this one.
12 quiz modules
One per chapter, open to everyone. After a mistake, the page of the book that explains it.
The quizzesA glossary of 120 terms
Every word in the book, explained in one sentence, and underlined in the text.
Open the glossaryA question?
On every page of the book, the assistant answers from the text and points you to the section that explains. For subscribers.
Between the page and the screen
In the evening, on the e-reader: the book and the website talk to each other
At every key moment, your copy of the book carries a code. Type it into the website, under “Book code”: the figure comes to life, the chapter quiz opens, the game starts. And on the website, every mistake in a quiz sends you back to the page of the book that explains it.
Bought on the website, your copy is numbered in your name, with a QR code that leads to your access. Keep it to yourself: to introduce others to the book, share the website’s address instead.
The approach
Why this book, and how it was made
Born in the field
Pierre Verley is a paraglider pilot and hiker. The book grew out of his own revision: to gather in a single volume what an independent pilot and a hiker need to understand about the sky in order to decide.
Written with AI, reviewed by a pilot
The outline, the texts and the figures were produced in dialogue with artificial-intelligence assistants, then reviewed and arbitrated by the author. The key figures have been cross-checked. Found an error? Please report it.
Free, then at a small price
The beginning is free; the rest is in the book and in the website subscription. Digital publishing has a cost: machines, a server, services, and above all time. Buying the book funds a project that is useful to many.
A word of caution. The figures are typical values, to be checked against your own terrain. This book replaces neither training, nor the day’s forecast, nor calling it off when the sky demands it. The author and the book
The contents
Four parts, from the cloud to the decision
Prelude and Part IUnderstanding the air
Part IIThe large scale
Part IIIThe mountains
Part IVDeciding
🔒: with the subscription, or a free month with the book. The full contents, with the preface and the appendices
How to get access
Start for free, carry on as you like
Without signing up: the preface, the prelude and chapters 1 and 2, all the quizzes, three games, the whole glossary and the beginning of the book in ePub. Start
The book
€6.99 once
In ePub, for your e-reader
- Your own copy, numbered in your name
- A month’s subscription to the website, free
Recommended
Subscription
€3 / month
Cancel at any time, with an invoice
- The whole book online, its 56 animations and the 9 games
- The book’s assistant
Yearly
€25 / year
Less than €2.10 a month
- Everything the subscription gives
- Cancel at any time, with an invoice
Supporter subscription
Pay what you likeevery month
The amount you choose
- Everything the subscription gives
- And a surprise, kept for those who give a little more
Digital publishing is not free: computers, a server, a connection, services, and above all time. Buying the book or subscribing funds a project that is useful to many pilots and hikers. Want to help more? A helping hand, once, for whatever amount you like.
The whole book
The book in ePub for your e-reader, €6.99: your own copy, numbered in your name, with a month’s subscription to the website free. Or the subscription alone, at €3 a month. Your first name, surname and e-mail address are all you need to open your account, with no password.
Buy the book The beginning in ePub, without signing up
Your data: what your name and address are used for.
Also available as an e-book from Amazon.
The whole book is open to you
You are a subscriber: the chapters, the animations, the games and the assistant are yours.
Your account is open
To read on, from fronts to the twelve typical days: the book in ePub, €6.99, with a month’s subscription free, or the website subscription, €3 a month or €25 a year.