METHANE AND NITROUS-OXIDE EMISSIONS - AN INTRODUCTION

Methane and nitrous oxide are important greenhouse gases. They contrib ute to global warming. To a large extent, emissions of methane and nit rous oxide are connected with the intensification of food production. Therefore, feeding a growing world population and at the same time con trolling these emissions is a great challenge. Important anthropogenic sources of biogenic methane are wet rice fields, cattle, animal waste , landfills and biomass burning. Important anthropogenic sources of bi ogenic nitrous oxide are land-use change, fertilizer production and us e and manure application. The ultimate objective of the Framework Conv ention on Climate Change implies a stabilization of greenhouse gas con centrations in the atmosphere. As a small first step towards achieving this objective, the Convention requires the industrialized countries to bring their anthropogenic emissions of greenhouse gases by 2000 bac k to 1990 levels. It was also agreed that all parties would make natio nal inventories of anthropogenic greenhouse gas emissions and programm es for control (UN, 1992). In this context, in February 1993 an intern ational workshop was held in Amersfoort in the Netherlands to discuss methods in national emission inventories for methane and nitrous oxide , and options for control (Van Amstel, 1993). A selection of the paper s presented in Amersfoort that focus on agricultural sources is publis hed in this volume. This introductory chapter gives background informa tion on biogenic sources and sinks of methane and nitrous oxide and op tions for their control. The goal of the Climate Convention is describ ed as well as the IPCC effort to develop an internationally accepted m ethodology for the monitoring of greenhouse gas emissions and sinks. F inally, some preliminary results from country inventories are given. I t is concluded that a common reporting framework and transparency of t he inventories are important to obtain comparable results that can be used for complying with the requirements of the Climate Convention and for facilitating the international debate about appropriate response