Improving urban weather, climate and air quality

Urban development may encourage people to move to cities. There are unprecedented benefits attributed to urban life. Better schools for the children, health facilities, and transportation are few that comes to mind immediately. Urbanization, if not planned well, has its own bad consequences. The IPCC report (2013), predicts that there will be extremes of climate like flooding, drought and storms. In connection with these effects of climate change, arbitrary urban planning only for the sake of urban development without consideration of those extremes of climate may lead to disaster. Urban flooding can easily occur due to ignorant urban development. It happens when water flows faster to urban region when there is no or little infiltration into the soil and surface obstacle that can hinder its rapid movement. There should be well built dikes, channels, and domes to protect water from flowing into the cities. Hard tile pavements, continuous asphalt, close to each other buildings res...

Dire Dawa is the second largest city in Ethiopia situated in the eastern part of the nation. Dechatu river crosses this city dividing it almost equally into the east and west portions. The river rises from the Ahmar Mountains and flows north towards the larger, and mostly used for irrigation, Awash river.  Even if the Dechatu flows towards the Awash river, it does not visibly empty into Awash river, rather it loses itself in the Cantur plain (Buren Meda) north of the city.    Figure 1. Dechatu river crossing Dire Dawa town dividing the city in to eastern and western portions.  Flash floods in urban Dire Dawa, Ethiopia happened many times in different years. In 2006 alone, 256 people reported to have lost their lives, 244 people disappeared, 10,000 people displaced, and houses, infrastructure, and livelihoods were damaged (ETV and VOA news,  2006).    Figure 2. Asphalt road in the middle of Dire Dawa town being ...

The main purpose of models is to represent the complex real system into simple mathematical equations and/or  computer simulations that is useful for (a) understanding the current scenario and establish the causality,  and (b) predicting the evolution of important variables into the future. So, models make studying an environmental system  easier but not simpler. Direct observations are costly, if possible, and prediction is based purely on  statistical techniques which may not use advances in the basic sciences. For example, to study weather and climate there are a number of ways. One method is directly going out into the field observe, photograph, film and draw whatever conclusion based on pure observation. Remote sensing is also part of the field observation. Observation data of such method can be employed for further statistical and/or laboratory analyses. Even though observation is regarded as the best method for obtaining accurate information about the enviro...