1 / 23

Projektübung Klimamodellierung

Projektübung Klimamodellierung. André Paul. Vorbesprechung. Projektübung Klimamodellierung (05-3034) – A. Paul. Veranstaltungsdaten. Veranstaltungskennziffer: 05-3034 ECTS-Punkte: 2.5 2 SWS, Mi von 13:00-15:00, GEO 1480/90. Website.

ruana
Download Presentation

Projektübung Klimamodellierung

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Projektübung Klimamodellierung André Paul

  2. Vorbesprechung Projektübung Klimamodellierung (05-3034) – A. Paul

  3. Veranstaltungsdaten • Veranstaltungskennziffer: 05-3034 • ECTS-Punkte: 2.5 • 2 SWS, Mi von 13:00-15:00, GEO 1480/90

  4. Website • http://www.palmod.uni-bremen.de/~apau/projektuebung/Material_zur_LV.html

  5. Inhalt • Einführung in die wissenschaftliche Programmierung anhand einfacher Beispielprogramme und ihrer schrittweisen Veränderung • Beschreibung des Klimasystems mit Hilfe von Erhaltungsgleichungen • Zeitliche und räumliche Diskretisierung von Erhaltungsgleichungen • Numerische Lösung diskretisierter Erhaltungsgleichungen auf einem Computer • Numerische Experimente mit physikalischen Ozean- und Atmosphärenmodellen

  6. Ziel • Einführung in die Methoden der Klimamodellierung und deren praktische Anwendung (weg vom Klimamodell als "black box")

  7. Bewertung • Anforderungen: selbstständige Lösung von Übungsaufgaben auf dem Computer (während der Übung/im Computerraum) • Referat

  8. Literatur • Stocker, T (2005) Skript zur Vorlesung „Einführung in die Klimamodellierung“, 141 Seiten, PDF (16 MB), korrigierte Version 15.2.2005 • http://www.climate.unibe.ch/~stocker/papers/skript0405.pdf

  9. Einführung in die wissenschaftliche Programmierung mit Fortran 90 • Verwendung von MATLAB o. ä. freigestellt • Schleifen, Lesen und Schreiben von Dateien, usw.

  10. Reading • The following notes are based on • Ellis, T.M.R., Phillips, Ivor R., and Lahey, Thomas M.: Fortran 90 Programming, Addison-Wesley Publishing Company.

  11. Telling a Computer What To Do • To get a computer to perform a specific task it must be given a sequence of unambiguous instructions or a program. • Generating a program: • Text file with instructions (Source Code; Fortran 90) • Translation into computer-compatible form (Compiler) • Executable Program

  12. The Linux look and feel • Cygwin is a Linux-like environment for Windows that consists of two parts: • A DLL (“Dynamic Link Library”, cygwin1.dll) • A collection of tools, which provide Linux look and feel • Link: http://www.cygwin.com

  13. A few useful Linux commands • pwd – print name of current/working directory • ls – list directory contents • cd – change directory • mkdir – make directories • rm – remove files or diretories • man – format and display the on-line manual pages (e.g. man pwd)

  14. How to start cygwin • Open cygwin window by double-clicking on the start_cygwin DOS batchfile provided with this exercise • If this does not work ...

  15. notepad hello.f90 & Creating and Running a Program • Invoke the editor from the Start menu, or type into the cygwin window to create a file called hello.f90.

  16. PROGRAM firsttry PRINT *,“hello“ END PROGRAM firsttry Creating and Running a Program • Type the following source code: • Compile by typing g95 hello.f90 (in the cygwin window) • Run the program by typing ./a.exe (g95 by default creates an executable called a.exe)

  17. Basic Fortran 90 concepts • All words which have a special meaning in Fortran are known as keywords. • Every main program unit must start with a PROGRAM statement which consists of the word PROGRAM followed by the name of the program as given by the programmer.

  18. Avoid implicit declaration • The special IMPLICIT NONE statement should always be placed immediately after the PROGRAM statement. It instructs the compiler that all variables must be declared before use.

  19. PROGRAM hydrostatic_balance IMPLICIT NONE ! Parameter declarations ! Variable declarations ! Executable statements END PROGRAM hydrostatic_balance Basic building blocks • A main program unit:

  20. ! Variable declarations ! k = loop variable ! p = pressure (Pa) ! dp = pressure change (Pa) INTEGER :: k REAL :: p,dp REAL and INTEGER variables • Use the INTEGER :: name statement to declare a whole-number variable • Use the REAL :: name statement to declare a floating-point variable

  21. ! Loop over vertical levels DO k=1,101 ! Block of statements p = p + dp END DO Repeating parts of your program

  22. Using files to preserve data • Connecting external files to your program • Connect a file to a unit by OPEN(UNIT=unit_number,FILE=file_name), where unit_number is an integer number, variable or parameter and file_name is a character expression.

  23. Using files to preserve data • Write a record to a file by WRITE (UNIT=unit_number,FMT=*) • Disconnect a file from a unit by means of a CLOSE (UNIT=unit_number) statement

More Related