Introduction

Climate Change and Variability, Extremes, Vulnerability, Impacts and Adaptation

There is now strong scientific evidence from both climate observations and model simulations that climate is changing both globally and regionally. According to IPCC (2013), global temperatures averaged over all land and ocean areas have risen by approximately 0.85 °C from 1880 to 2012. This has mainly been attributed to increasing emission and concentration of Greenhouse Gases (GHGs) especially Carbon dioxide (CO2) in the atmosphere attributed to anthropogenic activities. GHGs absorb and re-emit the earth’s out-going long wave radiation back to the earth’s surface. The net effect of this process is alteration of the earth’s energy budget leading to a net global warming and ultimately increase in surface temperatures. The increased energy in the atmosphere has systematically altered the nature of the drivers of the climate system at various scales and accelerated climate change.

Climate change events associated with sea level rise, heat waves, tropical cyclones, floods and droughts are increasingly becoming more intense and frequent over different parts of the world with catastrophic impacts to humanity and ecosystem including fauna and flora. These impacts associated with climate changes and variability under some scenarios have already devastating economic activities for developing countries that are ill-prepared cope and adapt to the current impacts. Projections from climate models indicate that the extremes will worsen in future with severe impacts. This has raised the concerns of governments and multinational agencies and development partners in terms of coping and adaptation mechanisms to climate change impacts across regions. Although there are both positive and negative effects of the changes in climate, with regards to the timing, intensity and frequency, the negative effects (cost) outweigh the positive effects (benefits).

The Greater Horn of Africa (GHA) region is characterized with high population growth that are faced with high incidence of climate related hazards due to heavy reliance on climate. A large part of the region falls within arid and semi-arid areas (ASALs) with mainly pastoral communities and small scale farmers. Observed rainfall records show declining trends in long rainfall (March to May) season that is a main rainfall season for the equatorial sector of the region. Moreover, rainfall over the region has become less predictable due to its complex nature. There are already identified climate change hotspots of concern in the region based on rainfall and temperature variability and trends.

The GHA region’s vulnerability to climate change and variability including extremes is quite high. This is due to high magnitudes of climate hazards, high sensitivity of socioeconomic activities and livelihoods (agriculture, water resources, energy among others) and low adaptive capacity already witnessed among communities. The low adaptive capacity is due to poor infrastructure, high illiteracy levels / poor access to information, low social capital, poor policies and early warning systems and poor governance.

More effort is needed to develop adaptation and mitigation strategies and technologies to effectively mitigate against the impacts of climate change. This is only possible reliable and timely climate information is availed to the key stake holders. ICPAC works to address the climate change issues over Greater Horn of Africa (GHA) region. Scientific information is generated from long series of both historic observed records and climate simulations of climate change using global and regional climate models. Plans are also underway to assess region-wide climate change impacts, vulnerability index mapping and adaptation assessments.
Under the proposed IGAD Regional Climate Change Strategy (IRCCS), the following topical areas are being addressed;
  • Observed Changes and Trends – Rainfall & Temperature
  • Observed Extremes – Rainfall & Temperature
  • Projected changes and Trends – Rainfall & Temperature
  • Projected Extremes – Rainfall & Temperature
  • Vulnerability, Impacts and Adaptation – Floods, Droughts, Food and Water Security
  • Capacity Building for Member States on Climate Change related Data and Tools